Question

Daal is now being sold at Rs. 20 a kg. During last month its rate was Rs. 16 per kg. By how much percent should a family reduce its consumption so as to keep the expenditure fixed?
1. 20 %
2. 40 %
3. 3%
4. 2%

Answer 1

Answer:

Step-by-step explanation:

(16/20)*100=80%

So,100-80=20%.

Answer 2

Given:

Rate of daal this month=Rs.20/kg

Rate of daal last month=Rs.16/kg

To find:

The percentage decrease in consumption so that the expenditure remains the same

Solution:

The percentage decrease in consumption so that the expenditure remains the same is 20%. (Option 1)

Let us assume that the consumption of the family last month was 10 kg.

Now, we are given that the rate of daal last month was Rs.16/kg.

The amount of expenditure can be calculated by multiplying the rate and consumption of last month.

Expenditure last month=Rate of daal last month×Consumption last month

Expenditure last month=16×10

Expenditure last month=Rs.160

We know that the expenditure has to remain the same this month as well.

So, the expenditure this month=Rate of daal this month×Consumption this month

On putting the values, we get

160=20×Consumption this month

Consumption this month=160/20

Consumption this month=8 kg

So, the decrease in consumption=Consumption last month-consumption this month

=10-8

=2 kg

So, the percentage decrease in consumption=(Decrease in consumption/Consumption last month)×100

=2/10 ×100

=20%

Therefore, the percentage decrease in consumption so that the expenditure remains the same is 20%.