In 4 days he spends 1/5 of his money to find unit amount per day 1/5 divided by 4 which equals 1/20 kyle spends 1/20 of his total money per day so after 14 days, he has spent 14/20 of his money 20/20-14/20=6/20 or the amount of money he has left 6/20=$30 if 6/20=$30, then 1/20 equals $5 (30/6) if 1/20 of Kyles money= $5 5*20= $100 kyle started with $100
4 days spending equal amounts so if x is how much he spends per day and y is the original amount then 4x=1/5y bc he has 4/5 left meaning what he spent was 1/5 of the original and after 10 more days which was 14 total he spent all but 30 so the total minus 30 will be how much kyle spent so 14x=y-30 which is y=(14x+30) and substitute that in for y in 4x=1/5y so 4x=1/5 (14x+30) 20x=14x+30 6x=30 x=5 and plug that in either of the original equations 4(5)=1/5y y=100 so he had $100 and spent $5 per day