Question

25. The price of coal rises by 20%. A family reduce the consumption of coal by 20% By
how much per cent will the expenses for coal of that family be increased or
decreased?​

Answer 1

Answer:

just follow this formula

•When something is increased

% change= (x /100+ x)* 100

• when something is decreased

% change= (x/100-x) * 100

Others content are not that much relevant apprantly in these types of peculiar questions....these 2 above formulas are enough to give you a headlong direction in a prudent mannerism..!

CP of coal = Rs x per kg

Quantity of coal consumed = m kg

Expenditure on coal = Rs mx

Increased CP of coal = Rs 1•2x

Increased over head expenditure = Rs 1•2mx

Let the reduced consumption of coal = m1 kg

Such that 1•2m1x = Mx

Or m1 = m/1•2

Reduction in consumption = m - m1 = 0•2m/1•2

Percentage reduction = 2/12*100 = 50/3 = 16•67%

Answer 2

Step-by-step explanation:

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