100% - 7% - 30% = 63% of people are on the sand
Q + d = 100 so q = 100 - d
0.25q + 0.10d = 19
substitute q = 100 - d into 0.25q + 0.10d = 19
0.25q + 0.10d = 19
0.25(100 - d) + 0.10d = 19
25 - 0.25d + 0.10d = 19
-0.15d = -6
d = 40
q = 100 - 40 = 60
answer
Kitara has 60 quarters and 40 dimes
If it is a slope formula I believe it is y= 4x-24