ANSWER KEYS - Teacher Use Only

Decimal Concepts | Grade 4

Student Concept Worksheet Answers
1
0.7
7/10 = 0.7 (seven tenths). One decimal place = tenths.
2
35/100
0.35 = 35/100 (thirty-five hundredths). Two decimal places = hundredths.
3
0.6 > 0.45
Rewrite 0.6 as 0.60. Compare: 60 hundredths > 45 hundredths. Or think: 60 cents > 45 cents.
4
0.50 (or 0.5); 1/2 (or 50/100)
50 squares shaded out of 100 = 50/100 = 0.50 = 0.5 = 1/2
Practice Worksheet Answers

Part A: Decimal Place Value

# Number Place Value
10.47tenths4 tenths or 0.4
20.53hundredths3 hundredths or 0.03
32.81tenths8 tenths or 0.8
41.06hundredths6 hundredths or 0.06

Part B: Convert Between Decimals and Fractions

# Given Answer Explanation
50.33/10One decimal place = tenths
60.7575/100 (or 3/4)Two decimal places = hundredths; simplifies to 3/4
79/100.9Nine tenths = 0.9
842/1000.42Forty-two hundredths = 0.42

Part C: Compare Decimals

# Comparison Answer Explanation
90.8 ? 0.80=0.8 = 0.80 (adding zeros doesn't change value)
100.25 ? 0.3<0.25 < 0.30 (25 hundredths < 30 hundredths)
110.09 ? 0.1<0.09 < 0.10 (9 hundredths < 10 hundredths)
120.50 ? 0.5=0.50 = 0.5 (same value)

Part D: Decimals on Number Lines

13
0.2, 0.35, 0.5, 0.75
Convert to hundredths: 0.20, 0.35, 0.50, 0.75. Order: 20, 35, 50, 75 hundredths
14
0.15, 0.45, 0.6, 0.9
Convert to hundredths: 0.15, 0.45, 0.60, 0.90. Order: 15, 45, 60, 90 hundredths

Challenge Questions:

#15: NO, Maria is incorrect. 0.30 and 0.3 are equal. Adding a zero to the right of a decimal does not change its value. Both equal 3 tenths or 30 hundredths.

#16: Possible answers include: 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59 (any three decimals between 0.50 and 0.60)

FAST Practice Quiz Answers
1
A) 0.35
35 squares shaded out of 100 = 35/100 = 0.35. The grid represents one whole divided into 100 parts.
2
B) 1/4
0.25 = 25/100 = 1/4 (divide both numerator and denominator by 25). Think: 25 cents = 1 quarter = 1/4 of a dollar.
3
C) 0.70 = 0.7
A) 0.8 < 0.18? NO - 0.80 > 0.18 (80 hundredths > 18 hundredths) X
B) 0.45 > 0.5? NO - 0.45 < 0.50 X
C) 0.70 = 0.7? YES - Adding zero doesn't change value Correct
D) 0.09 > 0.9? NO - 0.09 < 0.90 (9 < 90 hundredths) X
4
Select: 0.6, 0.55, and 0.75
0.49 - NOT greater than 0.5 (49 hundredths < 50 hundredths)
0.6 = 0.60 > 0.50 (60 hundredths > 50 hundredths)
0.05 - NOT greater than 0.5 (5 hundredths < 50 hundredths)
0.55 > 0.50 (55 hundredths > 50 hundredths)
0.75 > 0.50 (75 hundredths > 50 hundredths)
5
C) 7 hundredths
In 3.47, the 7 is in the second place after the decimal point, which is the hundredths place. Its value is 7/100 or 0.07.
6
B) Marcus has more money because 0.80 > 0.65
Compare: 80 cents > 65 cents. Therefore $0.80 > $0.65, so Marcus has more money.
FAST Quiz Scoring Guide
Score Interpretation Recommended Action
6/6 Mastery Ready for IXL practice on decimal operations. Consider extension to adding/subtracting decimals or decimals to thousandths.
4-5/6 Approaching Mastery Review missed concepts. Focus on place value or comparing, whichever was missed. Use money examples.
2-3/6 Developing Reteach with manipulatives (base-10 blocks, hundred grids). Use money heavily - pennies and dimes.
0-1/6 Needs Intervention Small group instruction starting with concrete models. Review fraction-decimal connection (1/10 = 0.1, 1/100 = 0.01).
Common Errors to Watch For
Error Example How to Address
Longer = Larger Thinking 0.15 > 0.9 Add zeros to compare: 0.15 vs 0.90. Use money: 15 cents vs 90 cents.
Confusing tenths/hundredths Reading 0.35 as "35 tenths" Count decimal places: 1 place = tenths, 2 places = hundredths.
Wrong fraction conversion Writing 0.3 as 3/100 The number of decimal places tells you the denominator: 1 place = 10, 2 places = 100.
Thinking 0.5 is not 0.50 Saying 0.5 < 0.50 Adding zeros after the last decimal digit doesn't change the value.