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
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