25% of what number is 21

Mathematics

1 answer:

chubhunter [2.5K]3 years ago

8 0

If we call the number "x" then:
x*25%=21
x*25/100=21
x=21*4
x=84

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To offer scholarships to children of employees, a company invests $13,000 at the end of every three months in an annuity that pa

Andreyy89

Annuities

Suppose a fixed investment R is done every fixed number of periods m per year for t years at a constant rate r.

The final value of the investments plus the interest is calculated as follows:

$FV=R\cdot\frac{(1+i)^n-1}{i}$

Where:

n = number of total periods of the investment.

n = m*t

$i=\frac{r}{m}$

The company invests R = $13,000 for t = 10 years at the end of every quarter (3 months), thus m = 4. The interest rate is r = 9% = 0.09.

The interest rate compounds quarterly.

Calculate:

n = 4*10 = 40

i = 0.09 / 4 = 0.0225

$\begin{gathered} FV=\$13,000\cdot\frac{(1+0.00225)^{40}-1}{0.0225} \\ FV=\operatorname{\$}13,000\times\frac{(1.00225)^{40}-1}{0.0225} \\ FV=\operatorname{\$}13,000\times\frac{2.435188965-1}{0.0225} \\ FV=\operatorname{\$}13,000\cdot63.786176 \end{gathered}$

Calculating:

FV = $829,220

The company will have $829,220 in scholarship funds

b. The interest can be found by subtracting the final value and the initial value. We have to calculate the latter: