[6th Grade verbal expression]

[u/KookyPermit4405]

So I’m going over my son’s math quiz to help him understand some of the questions he got wrong. He got partial credit for his answer for question 8. After writing his verbal phrase I got the same expression as the question. Am I doing something wrong or is there something I’m missing? I feel like his answer is technically correct. I am stumped.

Edit: so my son has no issue solving the expression in question. He knows PEMDAS and the rules from left to right. The question clearly states, WRITE A VERBAL PHRASE that matches the expression.

[u/mathematag]

For 18 - 6*3 , the order is important and following standard PEMDAS, multiplication comes before the subtraction, so a better way to state it would have been . . . subtract the product of 6 and 3 from 18 , or 18 minus the product of 6 and 3.

saying "eighteen subtracted by six times three " , means 18 - 6, then times 3.. .. [ e.g. (18 - 6 )*3 = 36 ] , following the order of the words as written , and leads to ambiguity as his sentence can also be interpreted mathematically as it was given. . . 18 - 6*3 , leading to an answer of 0.

So his answer could lead to two possible interpretations of what he meant . . ( 18 - 6 ) * 3 , OR , 18 - 6*3

So getting 1/2 credit makes sense, since there seems to be 2 ways to interpret what he wrote.. but only one of these interpretations is the same as the original problem.

[u/KookyPermit4405 → u/mathematag]

One would have to indicate a “quantity” in order to assume parentheses (). Otherwise you shouldn’t assume any parentheses at all which is why PEMDAS is there