Question

At what rate percent per annum will the simple interest on Rs 15000 be Rs 3000 in ? 2 1/2 years

Answer 1

Rate=8%

Explanation:

Step 1: Write the given terms

Principal (p)=Rs15000

Rate(r)=?

Time(t)=2 1/2=5/2=2.5

Interest(i)=Rs3000

Step 2: Write the formula for calculating Simple interest

`i = (p * r * t)/(100)`

Step 3: Make Rate(r) the subject of the equation in Step 2

`by \: cross \: multiplcation \\ 100i = prt \\ divide \: both \: sides \: by \: pt \: to \: have \\ (100i)/(pt) = r`

Step 4: Use the new equation for r to get the rate by substitution

`r = (100i)/(pt) \\ r = (100 * 3000)/(15000 * 2.5) \\ r = (300000)/(37500) \\ r = 8`

Hence, the rate of the simple interest is 8%