\left[x \right] = \left[ \frac{5\,y}{158}+\frac{6\,z}{79}\right][x]=[1585y+796z]
Just simple proportions:
12(apples) x(apples)
-------------- = --------------
4(oranges) 7(oranges)
12*7 = 84
84/4 = 21
There are 21 apples + 7 oranges = 28 apples and oranges!
The unit rate is 10:1 because unit rates are out of 1
You would find that by dividing 20 and 2 by the same number to get to one for this specific problem. 20 divided by two is ten and two divided by two is one. So that is your answer for part b. I can’t draw a graph however so sorry
Answer:
23,24,26,27 sorry if you get it wrong
For the average to be 90,
(99 + 93 + x) / 3 = 90
or 192 + x = 270
or x = 270 - 192 = 78
Jim must score at least 78 in the third test.