7 1/2÷ 1 9/10 = 15/2 ÷19/10 = 15/2x10/19 = 159/38 = 4 7/38
4 7/38 (Answer)
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38 )159
152
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Y=mx+b, m=(y2-y1)/(x2-x1)
m=(7-4)/(6--3)=3/9=1/3
y=x/3 +b, now use either point to solve for b, I'll use (6,7)
7=6/3 +b
7=2+b
b=5 so our line is:
y=x/3 +5 or more neatly...
y=(x+15)/3
equation : c=£1.25 for example to find out 3 cans : 3c= £1.25x3
34992/81 or 81*x=34992 = 432