Intrest

[storm vale]

1. Wait patiently for a helper to come along.
2. Once someone helps you, say thank you and close the thread with: ```diff
   +close

[silk wren]

Sure

Sorry for my lateness

Any specific question you need help on?

[silk wren]

I think what you need to do for Q8

Is that you need to divide the bigger number by the small number to get the percent per annum for the 2 years

I’m probably wrong though

[harsh isle]

Look up the compound interest formula

substitute the numbers and you'll get this

$774.4 = 640(1 + r)^2$

then the rest is just algebra