Grade 4 word problems worksheet on adding and subtracting decimals, illustrated with a chef.

Problem 1: Adding decimals

Question: There are 4.5 liters of milk in a pot. The chef adds 2.5 g of salt and 1.2 liters of water. How much liquid is in the pot?

#### Solution:
1. Identify the liquids in the pot:
- Milk: 4.5 liters
- Water: 1.2 liters

2. Salt is not a liquid, so it is not included in the total liquid calculation.

3. Add the volumes of the liquids:
\[
4.5 \, \text{liters} + 1.2 \, \text{liters} = 5.7 \, \text{liters}
\]

#### Final Answer:
\[
\boxed{5.7}
\]

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Problem 2: Subtracting decimals

Question: The chef took out 54.8 g of butter but then found out that he took out 6.9 g more than he needed. How much butter did he need?

#### Solution:
1. Understand the problem:
- The chef took out 54.8 g of butter.
- He took out 6.9 g more than he needed.

2. Set up the equation:
Let \( x \) be the amount of butter the chef actually needed.
\[
x + 6.9 = 54.8
\]

3. Solve for \( x \):
\[
x = 54.8 - 6.9
\]

4. Perform the subtraction:
\[
54.8 - 6.9 = 47.9
\]

#### Final Answer:
\[
\boxed{47.9}
\]

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Problem 3: Adding decimals

Question: The chef is making 10.5 batches of dinner rolls. For each batch, he kneads dough for 0.7 hours and lets the dough rest for 1.6 hours. Then he bakes the dough for 0.4 hours. How long does it take to make each batch of dinner rolls?

#### Solution:
1. Identify the time spent on each step per batch:
- Kneading: 0.7 hours
- Resting: 1.6 hours
- Baking: 0.4 hours

2. Add the times for one batch:
\[
0.7 \, \text{hours} + 1.6 \, \text{hours} + 0.4 \, \text{hours}
\]

3. Perform the addition:
\[
0.7 + 1.6 = 2.3
\]
\[
2.3 + 0.4 = 2.7
\]

#### Final Answer:
\[
\boxed{2.7}
\]

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Summary of Answers:

1. \( \boxed{5.7} \)
2. \( \boxed{47.9} \)
3. \( \boxed{2.7} \)