Question

Jacob bought a few cereal boxes, the total weight of which was 16 kg 800 g. If the weight of one cereal box is 420 g, find the number of boxes.

• A. 70
• B. 40
• C. 50
• D. 60

Answer 1

The correct option is B 40

$\text{Weight of cereal boxes bought}=16kg800g$
Weight of 1 cereal box = 420 g

∴ Number of cereal boxes bought = Weight of all cereal boxes ÷ Weight of 1 cereal box

Step 1:
Convert the total weight of the cereal boxes to a common unit (g).

$1\text{kg}=1000\text{g}$
$\Rightarrow 16\text{kg}=1000\times 16=16000\text{g}$


So, the total weight of the cereal boxes $\text{in grams is}16000g+800g=16800g$

Step 2:
Divide 16800 by 420 by long division method.

$$\begin{array}{c}40\\ 42016800\\ -\underset{–}{1680}\\ 0\\ -\underset{–}{0}\\ 0\end{array}$$

∴ Jacob bought 40 cereal boxes.