Find the rate at which naira 280, will earn naira 21.00k simple lnterest .
To find the rate at which Naira 280 will earn Naira 21.00k simple interest, you can use the formula for simple interest:
Simple Interest (SI) = (Principal (P) × Rate (R) × Time (T)) / 100
In this case, you have the principal (P) as Naira 280 and the simple interest (SI) as Naira 21.00k. To solve for the rate (R), you also need to know the time (T), which hasn't been provided.
Assuming the time is 1 year, you can use the formula as follows:
21 = (280 × R × 1) / 100
21 = 280 × R / 100
To find R, multiply both sides of the equation by 100:
21 × 100 = 280 × R
2100 = 280 × R
Now, divide both sides by 280:
R = 2100 ÷ 280
R = 7.5
So, the interest rate is 7.5%. Keep in mind that this calculation is based on the assumption that the time is 1 year. If the time is different, you can follow the same steps but replace the "1" in the equation with the given time (in years).