SSC CGL Tier1 Quantitative Aptitude Interest Test 3

Let sum = x

Time = 20 years

Simple Interest = x

$\text{R = }\dfrac{100 \times \text{SI}}{\text{PT}} = \dfrac{100 \times x}{x \times 20} = \dfrac{100}{20} = 5\%$

$\text{Time, T = (22 + 30 + 21)days = 73 days = }\dfrac{73}{365}\text{ year} = \dfrac{1}{5}\text{ year}$

$\text{Rate, R = }7\dfrac{1}{2}\% = \dfrac{15}{2}\%$

$\text{SI = }\dfrac{\text{PRT}}{100} = \dfrac{1820 \times \dfrac{15}{2} \times \dfrac{1}{5}}{100} = \dfrac{1820 \times \dfrac{3}{2} }{100} = \dfrac{910 \times 3}{100} = \dfrac{2730}{100}=27.30$

$\text{P} = \dfrac{100 \times \text{SI}}{\text{RT}} = \dfrac{100 \times 360}{12 \times 4} = \dfrac{100 \times 30}{4}= 25 \times 30 = 750$

Time from May 3rd to July 15th = 28 days of May + 30 days of June and 15 days of July

$\text{= 73 days= }\dfrac{73}{365}\text{ years = }\dfrac{1}{5}\text{ years}$

$\text{Simple interest = }\dfrac{\text{PRT}}{100}= \dfrac{500 \times 6 \times \dfrac{1}{5}}{100} =6$

Let the sub be Rs.x and the initial rate be R%.Then

$\dfrac{\text{x}\times (\text{R+4}) \times 2}{100} - \dfrac{\text{x}\times \text{R} \times 2}{100} = 60$

$\Rightarrow \dfrac{\text{x}\times 4 \times 2}{100} = 60$

$\Rightarrow \dfrac{\text{x} \times 2}{100} = 15$

$\Rightarrow 2x = 1500$

$\Rightarrow x = 750$

Let the sum of money be Rs.x

$\text{Amount after 4 years = }\dfrac{7x}{5}$

T = 4 years

R = ?

$\text{Simple Interest, SI = }\left(\dfrac{7x}{5} - x\right) = \dfrac{2x}{5}$

$\text{R = }\dfrac{100 \times \text{SI}}{\text{PT}} = \dfrac{100 \times \dfrac{2x}{5} }{x \times 4}= \dfrac{40}{4} = 10\%$

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Solution 1

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$\dfrac{3000 \times 5 \times \text{T}}{100} - \dfrac{2000 \times 5 \times \text{T}}{100} = 50$

$\left(3000-2000\right)\dfrac{5 \times \text{T}}{100} = 50$

$1000 \times \dfrac{5 \times \text{T}}{100} = 50$

$50 \text{T} = 50$

$\text{T} = 1\text{ year}$

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Solution 2

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Difference in principal = $\left(3000-2000\right)$ = 1000

i.e., Simple Interest on Rs.1000 will be Rs.50

$\dfrac{1000 \times 5 \times \text{T}}{100} = 50$

$50 \text{T} = 50$

$\text{T} = 1\text{ year}$

Principal amount is $15,000.

Rate of interest is 6%.

Counting the number of days from May 30 to August 10;

Note: Since May 30 is the beginning date, it is not included in counting.

May 31 1

June 1-30 30

July 1-31 31

August 1-10

10 Total 72 days

Converting days into years:

72 days x (1year360days) = 15years

Using the formula for solving the simple interest;

Interest = Principal x Rate x Time

Interest = $15,000 x 6% x 15

Interest = $15,000 x 0.06 x 15

Interest = $180

Therefore, the businessman will pay $180 interest.

Principal amount is $1,800.

Rate of interest is 8%.

Counting the number of days from December 25 to February 14;

Dec 25-31 6

Jan 1-31 31

Feb 1-14 14

Total 51 days

Converting days into years:

51 days x (1year365days) = 51365years

Using the formula for solving the simple interest;

Interest = Principal x Rate x Time

Interest = $1,800 x 8% x 51365

Interest = $1,800 x 0.08 x 51365

Interest = $20.12

Therefore, the Louie will pay $20.12 interest.

Principal amount is $800.

Rate of interest is 15%.

Time to pay the principal with the interest is 1 year.

Using the formula for solving the future amount;

Future Amount = Principal x [1 + (Rate x Time)]

Future Amount = $800 x [1 + (15% x 1)]

Future Amount = $800 x [1 + (0.15 x 1)]

Future Amount = $800 x (1 + 0.15)

Future Amount = $800 x 1.15

Future Amount = $920

Therefore, the employee must pay $920 in 1 year