You want to know the factor by which 3 2/3 is multiplied to get 7 1/3.
1. You can estimate that it is 2 from 7/3 ≈ 2, then check by multiplication to see if that is right.
.. 2*(3 2/3) = 6 4/3 = 7 1/3 . . . . 2 is the correct factor.
2. You can divide 7 1/3 by 3 2/3 to see what the factor is.
.. (7 1/3)/(3 2/3) = (22/3)/(11/3) = 22/11 = 2 . . . . 2 is the factor Earl used.
3. You could see how many times you can subtract 3 2/3 from 7 1/3.
.. 7 1/3 -3 2/3 = (7 -3) +(1/3 -2/3) = 4 -1/3 = 3 2/3 . . . . . subtracting once gives 3 2/3
.. 3 2/3 -3 2/3 = 0 . . . . . . subtracting twice gives 0, so the factor is 2.
4. You could add 3 2/3 to see how many times it takes to get 7 1/3.
.. 3 2/3 +3 2/3 = (3 +3) +(2/3 +2/3) = 6 +4/3 = 7 1/3
We only need to add two values of 3 2/3 to get 7 1/3, so the factor is 2.
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We have shown methods using multiplication, division, subtraction, addition. Take your pick.
For this problem, I'd use cross-multiplication.
9/12 = x/8.
When cross multiplying, multiply 12*x and 9*8. This leads to a new equation:
12x = 72.
Then you solve as an algebra problem.
*Divide 12 on both sides*
x = 6.
Four batches should be the correct answer
I think you have to combine like terms to solve this one. (6d - 3d) + (5 - 2) = 3d + 3
