Question
A man invested certain sum at simple interest of r% p.a.
such that it amounts to 160% of itself in 6 years. Find the interest earned when Rs. 2400 is invested at simple interest of r% p.a. for 3 years.Solution
Let the sum invested be Rs. ‘P’ Therefore, interest earned in 6 years = 1.6P – P = Rs. 0.6P ATQ; 0.6P = (P × r × 6) ÷ 100 Or, r = 60 ÷ 6 Or, r = 10 So, required interest earned = (2400 × 10 × 3) ÷ 100 = Rs. 720
252, 235, 220, 207, 196, ?
53 × 38 + 32 × âˆ›54872 = ?
152    142    122   ?     52    2
32, 52, 82, 124, 180, ?
124, 107, 91, ? , 62, 49
In each of the following number series, one term is missing. Find the missing term.
2, 6, 18, 54, 162, ?
15, 31, 67, 131, ?, 375
58   83   133   ?    308    433
99, 101, 107, 131, 251, ?
32   33    29   38    ?      47    11
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