Question
A certain sum of money at simple interest amounts to Rs
7200 in 3 years and Rs 8000 in 5 years. What is the rate of interest per annum?Solution
ATQ, Let principal = P, rate = r per year. Amount after 3 years: P(1 + 3r) = 7200 Amount after 5 years: P(1 + 5r) = 8000 Divide second by first: (1 + 5r) / (1 + 3r) = 8000 / 7200 = 10/9 9(1 + 5r) = 10(1 + 3r) 9 + 45r = 10 + 30r 15r = 1 ⇒ r = 1/15 = 6⅔% per annum.
4 5 12 39 160 ?
...31     35      60     124      ?      441
...48Â Â Â Â 61 Â Â Â Â 76 Â Â Â Â 94Â Â Â Â 116 Â Â Â Â Â ?
Three series are given below. You have to find the values of P, Q and R, then establish a relationship among them.
I:Â Â Â 210, P , 233, 64,...
12, 24, 72, 288, 1440, ?
19.11 × 5.98 + 20.03 × 3.12 – 34.95 + 97.9 × 3.02 =?
A’ is the nth term of the given series and ‘B’ is the (n + 1)th term of the given
series. Choose the correct statement from the following s...
130 114 106 102 100 ?
16     17      25      ?     99    180
...1, 27, ?, 343, 729, 1331
