Test questions for adding rational numbers (decimals) Grade 7

📚 Quick Study Guide

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• Rational Numbers: Numbers that can be expressed as a fraction $\frac{p}{q}$, where $p$ and $q$ are integers and $q \neq 0$. Decimals are rational numbers because they can be written as fractions.
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• Adding Decimals: Align the decimal points vertically, then add the numbers as you would with whole numbers. Carry over when necessary.
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• Adding Negative Decimals: If both decimals are negative, add their absolute values and keep the negative sign.
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• Adding Decimals with Different Signs: Subtract the smaller absolute value from the larger absolute value. The result has the sign of the decimal with the larger absolute value.
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• Tip: Use a number line to visualize adding rational numbers, especially when dealing with positive and negative numbers.

➕ Practice Quiz

1. What is $3.25 + 1.75$?
1. 4.00
2. 5.00
3. 5.25
4. 4.75
2. What is $-2.5 + (-1.5)$?
1. -4.0
2. 4.0
3. -1.0
4. 1.0
3. What is $5.8 - 2.3$?
1. 3.5
2. 8.1
3. 2.5
4. 7.5
4. What is $-4.6 + 2.1$?
1. -2.5
2. 2.5
3. 6.7
4. -6.7
5. What is $10.75 + (-5.25)$?
1. 5.50
2. 16.00
3. -5.50
4. -16.00
6. What is $-8.4 - 1.6$?
1. -10.0
2. 6.8
3. 10.0
4. -6.8
7. What is $7.9 + (-7.9)$?
1. 0
2. 15.8
3. -15.8
4. 1