Find the perimeter and area of the given geometric shapes.
Worksheet with six geometric shapes (rectangles and triangles) showing side lengths in centimeters, asking to find perimeter and area.
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Step-by-step solution for: Grade Perimeter Area Worksheet Kidschoolz, 56% OFF
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Show Answer Key & Explanations
Step-by-step solution for: Grade Perimeter Area Worksheet Kidschoolz, 56% OFF
To solve the problem, we need to calculate the perimeter and area for each of the given shapes. Let's go through each shape step by step.
---
#### Dimensions:
- Outer rectangle: \(76 \, \text{cm} \times 38 \, \text{cm}\)
- Inner rectangle (cut-out): \(24 \, \text{cm} \times 14 \, \text{cm}\)
#### Perimeter:
The perimeter of the outer rectangle is:
\[
P_{\text{outer}} = 2 \times (76 + 38) = 2 \times 114 = 228 \, \text{cm}
\]
The inner rectangle does not affect the perimeter since it is a cut-out. Therefore, the perimeter remains:
\[
\boxed{228 \, \text{cm}}
\]
#### Area:
The area of the outer rectangle is:
\[
A_{\text{outer}} = 76 \times 38 = 2888 \, \text{cm}^2
\]
The area of the inner rectangle is:
\[
A_{\text{inner}} = 24 \times 14 = 336 \, \text{cm}^2
\]
The area of the shape is the area of the outer rectangle minus the area of the inner rectangle:
\[
A = 2888 - 336 = 2552 \, \text{cm}^2
\]
\[
\boxed{2552 \, \text{cm}^2}
\]
---
#### Dimensions:
- Base: \(15 \, \text{cm}\)
- Height: \(58 \, \text{cm}\)
- Hypotenuse: \(29 \, \text{cm}\)
#### Perimeter:
The perimeter is the sum of all sides:
\[
P = 15 + 58 + 29 = 102 \, \text{cm}
\]
\[
\boxed{102 \, \text{cm}}
\]
#### Area:
The area of a triangle is given by:
\[
A = \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times 15 \times 58 = \frac{1}{2} \times 870 = 435 \, \text{cm}^2
\]
\[
\boxed{435 \, \text{cm}^2}
\]
---
#### Dimensions:
- Sides: \(52 \, \text{cm}\), \(58 \, \text{cm}\), \(29 \, \text{cm}\)
#### Perimeter:
The perimeter is the sum of all sides:
\[
P = 52 + 58 + 29 = 139 \, \text{cm}
\]
\[
\boxed{139 \, \text{cm}}
\]
#### Area:
We use Heron's formula to find the area. First, calculate the semi-perimeter \(s\):
\[
s = \frac{52 + 58 + 29}{2} = \frac{139}{2} = 69.5 \, \text{cm}
\]
Next, use Heron's formula:
\[
A = \sqrt{s(s-a)(s-b)(s-c)}
\]
where \(a = 52\), \(b = 58\), and \(c = 29\):
\[
A = \sqrt{69.5 \times (69.5 - 52) \times (69.5 - 58) \times (69.5 - 29)}
\]
\[
A = \sqrt{69.5 \times 17.5 \times 11.5 \times 40.5}
\]
Calculate step-by-step:
\[
69.5 \times 17.5 = 1226.25
\]
\[
11.5 \times 40.5 = 465.75
\]
\[
1226.25 \times 465.75 = 572,109.375
\]
\[
A = \sqrt{572,109.375} \approx 756.38 \, \text{cm}^2
\]
\[
\boxed{756.38 \, \text{cm}^2}
\]
---
#### Dimensions:
- Length: \(78 \, \text{cm}\)
- Width: \(68 \, \text{cm}\)
#### Perimeter:
The perimeter of a rectangle is:
\[
P = 2 \times (\text{length} + \text{width}) = 2 \times (78 + 68) = 2 \times 146 = 292 \, \text{cm}
\]
\[
\boxed{292 \, \text{cm}}
\]
#### Area:
The area of a rectangle is:
\[
A = \text{length} \times \text{width} = 78 \times 68 = 5304 \, \text{cm}^2
\]
\[
\boxed{5304 \, \text{cm}^2}
\]
---
#### Dimensions:
- Base: \(31 \, \text{cm}\)
- Equal sides: \(31 \, \text{cm}\)
- Height: \(42 \, \text{cm}\)
#### Perimeter:
The perimeter is the sum of all sides:
\[
P = 31 + 31 + 31 = 93 \, \text{cm}
\]
\[
\boxed{93 \, \text{cm}}
\]
#### Area:
The area of a triangle is:
\[
A = \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times 31 \times 42 = \frac{1}{2} \times 1302 = 651 \, \text{cm}^2
\]
\[
\boxed{651 \, \text{cm}^2}
\]
---
#### Dimensions:
- Base: \(25 \, \text{cm}\)
- Height: \(36 \, \text{cm}\)
- Hypotenuse: \(40 \, \text{cm}\)
#### Perimeter:
The perimeter is the sum of all sides:
\[
P = 25 + 36 + 40 = 101 \, \text{cm}
\]
\[
\boxed{101 \, \text{cm}}
\]
#### Area:
The area of a triangle is:
\[
A = \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times 25 \times 36 = \frac{1}{2} \times 900 = 450 \, \text{cm}^2
\]
\[
\boxed{450 \, \text{cm}^2}
\]
---
1. Rectangle with cut-out:
- Perimeter: \(228 \, \text{cm}\)
- Area: \(2552 \, \text{cm}^2\)
2. Triangle:
- Perimeter: \(102 \, \text{cm}\)
- Area: \(435 \, \text{cm}^2\)
3. Triangle:
- Perimeter: \(139 \, \text{cm}\)
- Area: \(756.38 \, \text{cm}^2\)
4. Rectangle:
- Perimeter: \(292 \, \text{cm}\)
- Area: \(5304 \, \text{cm}^2\)
5. Isosceles Triangle:
- Perimeter: \(93 \, \text{cm}\)
- Area: \(651 \, \text{cm}^2\)
6. Right Triangle:
- Perimeter: \(101 \, \text{cm}\)
- Area: \(450 \, \text{cm}^2\)
\[
\boxed{
\begin{array}{ll}
\text{1. Perimeter: } 228 \, \text{cm}, & \text{Area: } 2552 \, \text{cm}^2 \\
\text{2. Perimeter: } 102 \, \text{cm}, & \text{Area: } 435 \, \text{cm}^2 \\
\text{3. Perimeter: } 139 \, \text{cm}, & \text{Area: } 756.38 \, \text{cm}^2 \\
\text{4. Perimeter: } 292 \, \text{cm}, & \text{Area: } 5304 \, \text{cm}^2 \\
\text{5. Perimeter: } 93 \, \text{cm}, & \text{Area: } 651 \, \text{cm}^2 \\
\text{6. Perimeter: } 101 \, \text{cm}, & \text{Area: } 450 \, \text{cm}^2 \\
\end{array}
}
\]
---
Shape 1: Rectangle with a cut-out
#### Dimensions:
- Outer rectangle: \(76 \, \text{cm} \times 38 \, \text{cm}\)
- Inner rectangle (cut-out): \(24 \, \text{cm} \times 14 \, \text{cm}\)
#### Perimeter:
The perimeter of the outer rectangle is:
\[
P_{\text{outer}} = 2 \times (76 + 38) = 2 \times 114 = 228 \, \text{cm}
\]
The inner rectangle does not affect the perimeter since it is a cut-out. Therefore, the perimeter remains:
\[
\boxed{228 \, \text{cm}}
\]
#### Area:
The area of the outer rectangle is:
\[
A_{\text{outer}} = 76 \times 38 = 2888 \, \text{cm}^2
\]
The area of the inner rectangle is:
\[
A_{\text{inner}} = 24 \times 14 = 336 \, \text{cm}^2
\]
The area of the shape is the area of the outer rectangle minus the area of the inner rectangle:
\[
A = 2888 - 336 = 2552 \, \text{cm}^2
\]
\[
\boxed{2552 \, \text{cm}^2}
\]
---
Shape 2: Triangle
#### Dimensions:
- Base: \(15 \, \text{cm}\)
- Height: \(58 \, \text{cm}\)
- Hypotenuse: \(29 \, \text{cm}\)
#### Perimeter:
The perimeter is the sum of all sides:
\[
P = 15 + 58 + 29 = 102 \, \text{cm}
\]
\[
\boxed{102 \, \text{cm}}
\]
#### Area:
The area of a triangle is given by:
\[
A = \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times 15 \times 58 = \frac{1}{2} \times 870 = 435 \, \text{cm}^2
\]
\[
\boxed{435 \, \text{cm}^2}
\]
---
Shape 3: Triangle
#### Dimensions:
- Sides: \(52 \, \text{cm}\), \(58 \, \text{cm}\), \(29 \, \text{cm}\)
#### Perimeter:
The perimeter is the sum of all sides:
\[
P = 52 + 58 + 29 = 139 \, \text{cm}
\]
\[
\boxed{139 \, \text{cm}}
\]
#### Area:
We use Heron's formula to find the area. First, calculate the semi-perimeter \(s\):
\[
s = \frac{52 + 58 + 29}{2} = \frac{139}{2} = 69.5 \, \text{cm}
\]
Next, use Heron's formula:
\[
A = \sqrt{s(s-a)(s-b)(s-c)}
\]
where \(a = 52\), \(b = 58\), and \(c = 29\):
\[
A = \sqrt{69.5 \times (69.5 - 52) \times (69.5 - 58) \times (69.5 - 29)}
\]
\[
A = \sqrt{69.5 \times 17.5 \times 11.5 \times 40.5}
\]
Calculate step-by-step:
\[
69.5 \times 17.5 = 1226.25
\]
\[
11.5 \times 40.5 = 465.75
\]
\[
1226.25 \times 465.75 = 572,109.375
\]
\[
A = \sqrt{572,109.375} \approx 756.38 \, \text{cm}^2
\]
\[
\boxed{756.38 \, \text{cm}^2}
\]
---
Shape 4: Rectangle
#### Dimensions:
- Length: \(78 \, \text{cm}\)
- Width: \(68 \, \text{cm}\)
#### Perimeter:
The perimeter of a rectangle is:
\[
P = 2 \times (\text{length} + \text{width}) = 2 \times (78 + 68) = 2 \times 146 = 292 \, \text{cm}
\]
\[
\boxed{292 \, \text{cm}}
\]
#### Area:
The area of a rectangle is:
\[
A = \text{length} \times \text{width} = 78 \times 68 = 5304 \, \text{cm}^2
\]
\[
\boxed{5304 \, \text{cm}^2}
\]
---
Shape 5: Isosceles Triangle
#### Dimensions:
- Base: \(31 \, \text{cm}\)
- Equal sides: \(31 \, \text{cm}\)
- Height: \(42 \, \text{cm}\)
#### Perimeter:
The perimeter is the sum of all sides:
\[
P = 31 + 31 + 31 = 93 \, \text{cm}
\]
\[
\boxed{93 \, \text{cm}}
\]
#### Area:
The area of a triangle is:
\[
A = \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times 31 \times 42 = \frac{1}{2} \times 1302 = 651 \, \text{cm}^2
\]
\[
\boxed{651 \, \text{cm}^2}
\]
---
Shape 6: Right Triangle
#### Dimensions:
- Base: \(25 \, \text{cm}\)
- Height: \(36 \, \text{cm}\)
- Hypotenuse: \(40 \, \text{cm}\)
#### Perimeter:
The perimeter is the sum of all sides:
\[
P = 25 + 36 + 40 = 101 \, \text{cm}
\]
\[
\boxed{101 \, \text{cm}}
\]
#### Area:
The area of a triangle is:
\[
A = \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times 25 \times 36 = \frac{1}{2} \times 900 = 450 \, \text{cm}^2
\]
\[
\boxed{450 \, \text{cm}^2}
\]
---
Final Answers:
1. Rectangle with cut-out:
- Perimeter: \(228 \, \text{cm}\)
- Area: \(2552 \, \text{cm}^2\)
2. Triangle:
- Perimeter: \(102 \, \text{cm}\)
- Area: \(435 \, \text{cm}^2\)
3. Triangle:
- Perimeter: \(139 \, \text{cm}\)
- Area: \(756.38 \, \text{cm}^2\)
4. Rectangle:
- Perimeter: \(292 \, \text{cm}\)
- Area: \(5304 \, \text{cm}^2\)
5. Isosceles Triangle:
- Perimeter: \(93 \, \text{cm}\)
- Area: \(651 \, \text{cm}^2\)
6. Right Triangle:
- Perimeter: \(101 \, \text{cm}\)
- Area: \(450 \, \text{cm}^2\)
\[
\boxed{
\begin{array}{ll}
\text{1. Perimeter: } 228 \, \text{cm}, & \text{Area: } 2552 \, \text{cm}^2 \\
\text{2. Perimeter: } 102 \, \text{cm}, & \text{Area: } 435 \, \text{cm}^2 \\
\text{3. Perimeter: } 139 \, \text{cm}, & \text{Area: } 756.38 \, \text{cm}^2 \\
\text{4. Perimeter: } 292 \, \text{cm}, & \text{Area: } 5304 \, \text{cm}^2 \\
\text{5. Perimeter: } 93 \, \text{cm}, & \text{Area: } 651 \, \text{cm}^2 \\
\text{6. Perimeter: } 101 \, \text{cm}, & \text{Area: } 450 \, \text{cm}^2 \\
\end{array}
}
\]
Parent Tip: Review the logic above to help your child master the concept of 5th grade area math worksheet.