Rs. 21750 is invested by a person in the bank account of his two sons whose ages are 9 years and 13 years in such a way that they will get equal amount at an age of 21 years at the rate of 4.5% per annum. Find the share of younger son.
Answer & explanation
Correct answer: option 1
Let the share of younger son = P1
share of elder son = P2
Time for younger son = 21 - 9 = 12
Time for elder son = 21 - 13 = 8
effective R% for younger son = 12 × 4.5% = 54%
effective R% for elder son = 8 × 4.5% = 36%
P1 × \(\frac{154}{100}\) = P2 × \(\frac{136}{100}\)
\(\frac{P_1}{P_2}\) = \(\frac{136}{154}\) = \(\frac{68}{77}\)
P1 P2
68 77 = 145
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× 150 × 150
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10,200 21,750