Question

Sarah has a savings account that earns `3/4%` interest per year. If Sarah has $840 in her account, what is the best estimate for the interest earned after 1 year?

Answer 1

After one years for 3/4 % interest on about 840$ you got 6.3 $

so $840 + $6.3 = $846.3 for the first year !

hope you understand the explaination ! have good day !

Explanation:

x = money base = $840

y = best estimate for the intrest earned after 1 year = 0.75% from X

f = best estimate for the intrest earned after 1 year + the money base

3/4 % = 0.75%

Solution to determine y :

`"1. "0.75/100 -= y/840 color(red)(larr" by ratio ")`
`color(white)()`

`"2. "y=(0.75xx840)/100`
`color(white)()`

`"3. "y=(630)/100`
`color(white)()`

`"4. "y=$6.3`

so : final equation :`" " f = x + (0.75)/100 x`

Note : dont forget that the number of the money in sarah account is different each years

exemple :

first year = $840

second year = $840 + 3/4% of $840 = $846.3

third year = $846.3 + 3/4% of $846.3 = $852.64