correct answer is: b) 2\;:\;5

Explanation

Here, 1 kg rice cost ₹ 40.
And, 1 kg of pulse costs ₹ 100.
\therefore Price of rice and pulse ratio is =\large\frac{40}{100} or \large\frac{2}{5}
\rightarrow 2\;:\;5
Ans: 2\;:\;5 is the ratio of rice and pulse cost.

Other variants of this particular math question are:

1. If the cost of 1 kilogram of rice is ₹ 40 and the cost of 1 kilogram of pulse is ₹ 100, what is the ratio of the prices of rice to pulse?
2. When 1 kilogram of rice is priced at ₹ 40 and 1 kilogram of pulse is priced at ₹ 100, what is the ratio between the prices of rice and pulse?
3. If the cost of 1 kilogram of rice amounts to ₹ 40 and the cost of 1 kilogram of pulse amounts to ₹ 100, what ratio represents the prices of rice to pulse?