Question

Question 4(a)

Determine if the following ratios form a proportion. Also, write the middle terms and extreme terms where the ratios form a proportion:

25 cm : 1 m and Rs. 40 : Rs. 160

Answer 1

In a statement of proportion, the four quantities involved when taken in order are known as respective terms. First and fourth terms are known as extreme terms. Second and third terms are known as middle terms.

First ratio: 25 cm : 1 m = 25 cm : (1 $\times$100) cm = 25 cm : 100 cm = $\frac{25}{100}=\frac{1}{4}=1:4$ [$\because$ 1 m = 100 cm]

Second ratio: Rs. 40 : Rs. 160 = $\frac{40}{160}=\frac{1}{4}=1:4$

The ratios are equal, therefore these are in proportion

i.e. 25 cm : 1 m :: Rs. 40 : Rs. 160

Middle terms = 1 m, Rs. 40

Extreme terms = 25 cm, Rs. 160