Question

2A mixture of paint is prepared by mixing $1$ part of red pigments with $8$ parts of base. In the following table, find the parts of base that need to be added

Parts of red pigment	$1$	$4$	$7$	$12$	$20$
Parts of base	$8$	$\cdots$	$\cdots$	$\cdots$	$\cdots$

If $1$ part of a red pigment requires $75$ mL of base, how much red pigment should we mix with $1800$ mL of base?

Answer 1

$1$ part $\Rightarrow 75$ ml base

$\therefore x$ part $\Rightarrow 1800$ml base

So, $\frac{x}{1800}$ $=\frac{1}{75}$

$\Rightarrow x=\frac{1\times 1800}{75}$

$\Rightarrow x=24$ ml