Cody has $700 in a svings account that pays 4% simple intrest. how much will he have in 1 year

Well, to calculate simple interest, it's pretty...well, simple
First, turn the 4% into a decimal by moving the percent sign over 2 spots, and replacing it with a decimal point. This gives you .04
Now, take 700 and multiply it by .04
This gives you 28. Now, this means he will be GAINING this much in a year, but we still have to add it back to the 700 to get your final answer of how much she will have.
700+28=728
He will have $728 in his account within 1 year of time, at 4% simple interest rate.
~Hope this helps!