you saved $100 in 5 months. At this rate, how much will you save in 15 months? what is the effect of your savings, if you save $110 in 5 months?
If you save $100 in 5 months, you are saving $100/5 = $<<100/5=20>>20 per month.
Therefore, in 15 months, you will save $20/month x 15 months = $<<20*15=300>>300.
If you save $110 in 5 months, you are saving $110/5 = $<<110/5=22>>22 per month.
Therefore, in 15 months, you will save $22/month x 15 months = $<<22*15=330>>330.
The effect of saving $110 instead of $100 in 5 months is that you will save an additional $110 - $100 = $<<110-100=10>>10.
Thus, the effect of your savings would be $10 in 5 months.