Question

Can someone help me set out this math problem I have trouble putting it out into an algebraic expression

First class postage is 25 cents for the first once and 20 cents for each additional ounce. How many additional ounces are you being charged for if the postage is $1.05

Answer 1

You start with .25. Then .20 (.20x) for each additional
0.25 + 0.20x = 1.05
Then, you subtract .25 from 1.05, which equals .8
After, you divide .8 by .2, which is 4. So the answer is 4.