ANSWER : Rs 10

Explanation : : Difference between Compound Interest and Simple Interest for 2 years=pr² p=Rs 4000;r=5% Difference=4,000 x 5/100 x 5/100=Rs 10

ANSWER : 50 kmph

Explanation : : Average speed = 4 /(1/25+1/50+1/75+1/150)=50 kmph

ANSWER : 32%

Explanation : : Cost price of 1200 gms=s.p of 1000 gms =12,000 C.P of 1 gm=10 Profit=20% Again he marks up his cost price by 10% Net profit percentage=10+20+(10*20)/100=32%

ANSWER : Rs 40

Explanation : : Difference in two selling price=(10%-(-20%)) =30% of cost price Actual difference in two selling price=Rs 12 Cost price=12 x 100 /30 x 100=Rs 40

ANSWER : increase by 1

Explanation : : x+(n+1)+(x+2)+(x+3)+(x+4)=5n =>5x+10=5n =>x=(n-2) Average of 7 consecutive numbers=(5x+10)+(x+5)+(x+6) / 7 =7x+21 / 7=x+3 New average=(n-2+3)=n+1 The average increases by 1