Alright so if you go to a bank put in $800 and it has a 5% interest per month for 10 months here's how you find the answer: (Scroll down to the bottom to get your answer if you don't want to know the entire process to get this answer)
First you got to find the number that is 5% of $800. This can be done like so:
$800 / 5 = $160 which is 5% of $800.
$800 + 16- = $960 for $800 being in the bank for 1 month.
Next you got to find the number that is 5% of 960. This can be done like this:
$960 / 5 = 192 which is 5% of $960.
$960 + 192 = $1,152 for $800 being in the bank for 2 months.
Next you got to find the number that is 5% of 1,152 now. This can be done like this:
$1,152 / 5 = 230.2 which is 5% of $1,152.
$1,152 + 230.4 = $1,382.4 for $800 being in the bank for 3 months.
I will speed this up for you now:
$1,382.4 / 5 = 276.48(5% of 1,382.4)
$800 in for 4 months = $1,658.88
$1,658.88 / 5 = 331.776
$800 in for 5 months = $1,990.656
$1,990.656 / 5 = 398.1312
$800 in for 6 months = $2,388.7872
$2,388.7872 / 5 = 477.75744
$800 in for 7 months = 2,866.54464
$2,866.54464 / 5 = 573.308928
$800 in for 8 months = $3,439.853568
3,439.853568 / 5 = 687.9707136
$800 in for 9 months = $4,127.8242816
$4,127.8242816 / 5 = 825.56485632
Finally if $800 dollars was in for 10 months your answer would be(If my math is correct):
$4,953.38913792
Estimated(by tenths):
$4,953.4
Estimated(by units):
$4,953 dollars.
Hope this helps! G'day!