I'll solve each problem step by step, finding the missing side using proportions for similar figures.
Problem 1:
Large rectangle: 48 × 40
Small rectangle: 12 × x
Setting up proportion: 48/12 = 40/x
4 = 40/x
x = 40/4 = 10
Problem 2:
Small rectangle: 3 × 2
Large rectangle: x × 10
Setting up proportion: 3/x = 2/10
Cross multiply: 3(10) = 2(x)
30 = 2x
x = 15
Problem 3:
Large rectangle: 108 × 81
Small rectangle: x × 9
Setting up proportion: 108/x = 81/9
108/x = 9
x = 108/9 = 12
Problem 4:
Small rectangle: 6 × x
Large rectangle: 72 × 54
Setting up proportion: 6/72 = x/54
Cross multiply: 6(54) = 72(x)
324 = 72x
x = 324/72 = 4.5
Problem 5:
Large rectangle: 72 × 60
Small rectangle: 6 × x
Setting up proportion: 72/6 = 60/x
12 = 60/x
x = 60/12 = 5
Problem 6:
Large rectangle: 20 × x
Small rectangle: 4 × 10
Setting up proportion: 20/4 = x/10
5 = x/10
x = 50
Problem 7:
Large triangle: base 36, side 44
Small triangle: base 9, side x
Setting up proportion: 36/9 = 44/x
4 = 44/x
x = 44/4 = 11
Problem 8:
Large triangle: base 24, side 22
Small triangle: base 12, side x
Setting up proportion: 24/12 = 22/x
2 = 22/x
x = 22/2 = 11
Final Answer:
1) x = 10
2) x = 15
3) x = 12
4) x = 4.5
5) x = 5
6) x = 50
7) x = 11
8) x = 11
Parent Tip: Review the logic above to help your child master the concept of similar figures proportions worksheet.