Cost of milk per carton = $ 70 cents = 70/100 = $0.7
Cost of bread per loaf = $60 cents = 60/100 = $0.6
Cost of cereals per box = $50 cents = 50/100 = $0.5
Cost of meat per pound = $1.50
If x is the number of cartons of milk bought, then
Number of loafs = x/2
Number pf boxes of cereals = x/2 +1
Number of pounds of meat = x/2 +1
Therefore,
0.7*x + 0.6*x/2 + 0.5 (x/2+1) + 1.5 (x/2+1) = 10
0.7x + 0.3x + 0.25x + 0.5 + 0.75x + 1.5 = 10
2x + 2 =10
2x = 8
x = 4
Substituting;
Milk cartons = 4
Number of bread = 4/2 = 2
Boxes of cereals = 2+1 = 3
Pounds of meat = 3
Replace X with -2 then solve:
(-2) +3 / (-2)-1
1 / -3 which is rewritten as -1/3
So, this is the answers you get from plugging in x = (7 through 10)
x = 7 ... 24
x = 8 ... 36
x = 9 ... 50
x = 10 ... 66
Then you get the rate of changes...
66 - 50 = 16
50 - 36 = 14
36 - 24 = 12
So the average of 16, 14 and 12 (those values added together and then that total divided by the number of values, which is 3) is 14
The average rate of change is 14
