Multiplying and Dividing Decimals: math test solutions, Grade 5 – download the PDF

1 Powers of 10 / 4 pts

1. \(6.28 \times 10 = 62.8\) (1 pt)
2. \(0.053 \times 100 = 5.3\) (1 pt)
3. \(9.4 \div 100 = 0.094\) (1 pt)
4. \(2{,}700 \div 1{,}000 = 2.7\) (1 pt)

2 Multiplying decimals / 4 pts

1. \(26 \times 7 = 182\), one place: \(18.2\) (1 pt)
2. \(45 \times 6 = 270\), two places: \(2.70 = 2.7\) (1 pt)
3. \(12 \times 8 = 96\), two places: \(0.96\) (1 pt)
4. \(35 \times 4 = 140\), three places: \(0.140 = 0.14\) (1 pt)

3 Place the decimal point / 3 pts

1. 1 + 1 = 2 places: \(10.81\) (1 pt)
2. 2 + 0 = 2 places: \(10.81\) (1 pt)
3. 1 + 3 = 4 places: \(0.1081\) (1 pt)

4 Division / 3 pts

1. \(18.4 \div 4 = 4.6\), since \(4.6 \times 4 = 18.4\) (1 pt)
2. \(54\) hundredths \(\div 6 = 9\) hundredths, so \(0.09\) (1 pt)
3. \(15 \div 0.3 = 150 \div 3 = 50\) (1 pt)

5 Area model / 3 pts

Shade a rectangle that is 4 squares wide and 8 squares tall (1 pt). It contains \(4 \times 8 = 32\) little squares (1 pt). Each square is 0.01, so \(0.4 \times 0.8 = 0.32\) (1 pt).

6 Training for a race / 3 pts

1. \(1.75 \times 6 = 10.5\) miles (1 pt)
2. \(12 - 10.5 = 1.5\) miles (1 pt)
3. \(1.5 \div 3 = 0.5\) mile each day (1 pt)