**Question 6**:

The mass of a box containing 6 papayas is 21.32 kg. The mass of the box when it is empty is 1.46 kg.

Calculate the average mass, in g, of a papaya.

*Mass of 6 papayas*

**Solution**:= 21.32 – 1.46

= 19.86 kg

Average mass of a papaya

= 19.86 ÷ 6

= 3.31 kg

= 3.31 × 1000 g

=

**3310 g**

**Question 7**:

Louis bought 600 g of cookies. Dennis bought twice the mass of cookies that Jackson bought. They bought 1.35 kg of cookies altogether. Calculate the mass, in g, of cookies bought by Jackson.

*Let Jackson bought*

**Solution**:*w*g of cookies.

600 g + 2 ×

*w*+

*w*= 1.35 kg

600 g + 3

*w*= 1.35 kg

600 g + 3

*w*= 1350 g

3

*w*= 1350 g – 600 g

*w*= 750 g ÷ 3

*w***= 250 g**

**Question 8**:

If the mass of 4 packets of candies is 2.6 kg, what is the mass of 9 packets of the same candies, in kg?

**Solution**:$\begin{array}{l}\text{Massof4packetsofcandies=2}\text{.6kg}\\ \text{Massof9packetsofcandies}=\frac{2.6}{4}\times 9\\ \text{}=5.85\text{kg}\end{array}$

**Question 9**:

It is given that $\frac{1}{4}$ of fruits is supplied to Juice Stall

*A*and $\frac{2}{7}$ to Juice Stall

*B*. The remaining 133.25 kg is sold to a fruit stall.

Calculate the mass of fruits that has been supplied to Fruit Stall

*B.*

**Solution**:$\begin{array}{l}\frac{1}{4}+\frac{2}{7}=\frac{7}{28}+\frac{8}{28}\\ \text{}=\frac{15}{28}\\ \text{Remainingfruitssoldtofruitstall}\\ =1-\frac{15}{28}\\ =\frac{13}{28}\\ \\ \text{Totalmassoffruits}\\ =\frac{28}{13}\times 133.25\\ =287\text{kg}\\ \\ \text{MassoffruitssuppliedtoJuiceStall}B\\ =\frac{2}{7}\times 287\\ =82\text{kg}\end{array}$

**Question 10**:

The mixture of metal to produce a piece of 50 sen coin are $\frac{2}{3}\text{zinc,}\frac{1}{5}\text{nickel}$ and the rest is copper.

If the mass of copper is 1.6 g, find the total mass, in g, of zinc and nickel.

**Solution**:$\begin{array}{l}\text{Fractionofcopper}\\ =1-\frac{2}{3}-\frac{1}{5}\\ =\frac{15}{15}-\frac{10}{15}-\frac{3}{15}\\ =\frac{2}{15}\\ \\ \text{Portionofcopper=2g}\\ \text{Portionofzincandnickel=13g}\\ \\ 2\leftrightarrow 1.6\text{g}\\ \text{Totalmassofzincandnickel},\\ 13\leftrightarrow \frac{13\times 1.6}{2}=10.4\text{g}\end{array}$