At simple interest, a man made a deposit of some money in...
At simple interest, a man made a deposit of some money in the bank. The amount in his bank account after 10 years is three times the money deposited. If the interest rate stays the same, after how many years will the amount be five times the money deposited?
15 years
25 years
20 years
30 years
Correct answer is C
Amount (A) = Principal (P) + Interest (I) i.e. A = P + I
1 = PTR100
A = 3P; T = 10 years (Given)
Since A = P + I
⟹3P=P+P×10×R100
⟹3P=P+10PR100
⟹3P=P+PR10
⟹3P−P=PR10
⟹2P=PR10
⟹2P1=PR10
⟹ PR = 20P
∴ R = 20%
Since the rate stays the same
A = 5P; R = 20%;T =?; A =P + I
\implies 5P = P + \frac {p \times T \times 20}{100}
\implies 5P - P = \frac {2PT}{10}
\implies 4P = \frac {2PT}{10}
\implies 2P = \frac {PT}{10}
\implies PT = 20P
\therefore T = 20 years
If y = (1 + x)2, find \frac{dy}{dx}...
Arrange \frac{3}{5},\frac{9}{16}, \frac{34}{59} and \frac{71}{97} in ascending ...
Simplify 2.04 × 3.7 (Leave your answer in 2 decimal place) ...
In the diagram, PQ is the diameter of the circle and ∠PRS = 58°. Find ∠STQ. ...
In the diagram below, O is the center of the circle if ∠QOR = 290o, find the size ∠QPR ...
The mean of the numbers 1.2, 1.0, 0.9, 1.4, 0.8, 0.8, 1.2 and 1.1 is ...