This grade 4 decimals worksheet answer key solves all 24 problems of the decimal fractions and decimal notation worksheet step by step.
Every solution shows how a fraction becomes a decimal, how tenths are renamed as hundredths, and how decimals are compared. Check each step against your own work, and find the first step where your answer differs from the key.
Grade 4 Decimals Worksheet Answer Key: problems 1–5
Problem 1: Shaded tenths
The strip has 10 equal parts and 6 are shaded.
\( rac{6}{10} = 0.6\)
Answer: \( rac{6}{10} = 0.6\)
Problem 2: Shaded hundredths
Four full rows are 4 tenths, and 5 more squares are 5 hundredths: \( rac{4}{10} + rac{5}{100} = rac{45}{100}\).
Answer: \( rac{45}{100} = 0.45\)
Problem 3: Tenths to decimal
Eight tenths has the 8 in the tenths place.
Answer: \(0.8\)
Problem 4: Decimal to tenths
The 9 is in the tenths place, so the denominator is 10.
Answer: \( rac{9}{10}\)
Problem 5: Hundredths to decimal
Twenty-three hundredths: 2 tenths and 3 hundredths.
Answer: \(0.23\)
Grade 4 Decimals Worksheet Answer Key: problems 6–10
Problem 6: Decimal to hundredths
The 7 is in the hundredths place, so the denominator is 100.
Answer: \( rac{7}{100}\)
Problem 7: Tenths as hundredths
\( rac{4}{10} = rac{4 \times 10}{10 \times 10} = rac{40}{100}\)
As a decimal, \( rac{40}{100} = 0.40 = 0.4\).
Answer: \( rac{40}{100} = 0.4\)
Problem 8: Decimal as hundredths
Six tenths is the same as 60 hundredths because \( rac{6}{10} = rac{60}{100}\).
Answer: \( rac{60}{100}\)
Problem 9: Place value chart
The 5 is in the ones place, so it is worth 5.
The 3 is in the tenths place, so it is worth \(0.3 = rac{3}{10}\).
The 8 is in the hundredths place, so it is worth \(0.08 = rac{8}{100}\).
Answer: \(5 + 0.3 + 0.08 = 5.38\)
Problem 10: Expanded form
There are 2 ones, 4 tenths, and 9 hundredths.
Answer: \(2.49\)
Grade 4 Decimals Worksheet Answer Key: problems 11–15
Problem 11: Tenths plus hundredths
\( rac{3}{10} = rac{30}{100}\)
\( rac{30}{100} + rac{5}{100} = rac{35}{100} = 0.35\)
Answer: \( rac{35}{100} = 0.35\)
Problem 12: Adding fractions with different denominators
\( rac{2}{10} = rac{20}{100}\)
\( rac{20}{100} + rac{47}{100} = rac{67}{100}\)
Answer: \(0.67\)
Problem 13: Point on a number line
The line from 0.3 to 0.4 has 10 equal steps, so each step is 0.01. Point P is 7 steps after 0.3.
Answer: \(0.37 = rac{37}{100}\)
Problem 14: Compare 0.4 and 0.38
Write 0.4 as 0.40. Forty hundredths is more than thirty-eight hundredths.
Answer: \(0.4 > 0.38\)
Problem 15: Compare 0.09 and 0.9
0.09 is 9 hundredths. 0.9 is 9 tenths, or 90 hundredths.
Answer: \(0.09 < 0.9\)
Grade 4 Decimals Worksheet Answer Key: problems 16–20
Problem 16: Same amount?
Each grid has 30 of 100 squares shaded. Three tenths and thirty hundredths cover the same amount: \( rac{3}{10} = rac{30}{100}\).
Answer: No, \(0.3 = 0.30\)
Problem 17: Order four decimals
As hundredths: 0.50, 0.45, 0.54, 0.05.
The order is 5, 45, 50, 54 hundredths.
Answer: \(0.05, 0.45, 0.5, 0.54\)
Problem 18: Dimes and pennies
A dime is \( rac{1}{10}\) of a dollar. A penny is \( rac{1}{100}\) of a dollar.
\( rac{3}{10} + rac{6}{100} = rac{30}{100} + rac{6}{100} = rac{36}{100}\)
Answer: \( rac{36}{100}\) of a dollar, or $0.36
Problem 19: Who ran farther?
Write 0.7 as 0.70. Seventy hundredths is more than sixty-five hundredths.
Answer: Ethan ran farther, \(0.70 > 0.65\)
Problem 20: Rainy days
\(0.3 = 0.30 > 0.28\), so Monday had more rain.
\( rac{3}{10} + rac{28}{100} = rac{30}{100} + rac{28}{100} = rac{58}{100} = 0.58\)
Answer: Monday; 0.58 inch in all
Grade 4 Decimals Worksheet Answer Key: problems 21–24
Problem 21: School garden
Tomatoes: \( rac{27}{100} = 0.27\).
Carrots: \( rac{3}{10} = rac{30}{100} = 0.30\). Carrots cover more because 0.30 > 0.27.
\( rac{27}{100} + rac{30}{100} = rac{57}{100} = 0.57\)
Answer: Carrots cover more; 0.57 of the garden is planted
Problem 22: Bike rides in order
As hundredths: 0.80, 0.75, 0.08.
Shortest to longest: 0.08, 0.75, 0.8.
The longest is 0.8 = \( rac{8}{10}\).
Answer: \(0.08, 0.75, 0.8\); longest \( rac{8}{10}\) mile
Problem 23: Bake sale cookies
Chocolate chip: \( rac{3}{10} = rac{30}{100} = 0.30\). Oatmeal: \( rac{24}{100} = 0.24\).
There were more chocolate chip because 0.30 > 0.24.
\( rac{30}{100} + rac{24}{100} = rac{54}{100} = 0.54\)
Answer: Chocolate chip; 0.54 of the cookies
Problem 24: Ribbon for a gift
\( rac{7}{10} = rac{70}{100}\)
\( rac{70}{100} + rac{15}{100} = rac{85}{100} = 0.85\) yard.
She needs 0.9 = 0.90 yard, and \(0.85 < 0.90\). She is short by \( rac{90}{100} – rac{85}{100} = rac{5}{100}\) yard.
Answer: No; she needs \(0.05\) yard more
How to use this grade 4 decimals worksheet answer key
Read this grade 4 decimals worksheet answer key after trying each problem yourself, and redo any problem you missed.
See every chapter on the Grade 4 math page.