starts with the multiplication, because there are no exponents or parentheses.
13 -6 +4/4 +4
Next is the division:
13 -6 +1 +4
Finally, the addition and subtraction:
7 +1 +4
8 +4
12
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We have assumed your x is not a variable, but is intended to indicate multiplication. We have also assumed that your "divided by" implies no particular grouping, so that the numerator is the first preceding number and only the first following number is in the denominator.
He will need to save up for 12 weeks because he is getting 2 dollars a week. It says after 3 weeks he saved 6, so divide six by three and the answer meaning he makes 2 a week. Next divide 24 by 2 and you get 12.
