I'm trying to help my daughter with math and having troble with the best way to help her so she understands it.
I'm trying to help my daughter with math and having troble with the best way to help her so she understands it.
Chris,
The problem here is interpret the words into something you can calculate. The phrase "18 and 7 plus 5" means that you are to add 7 and 5 before multiplying by 18. An easy mistake is think it means to add 18 and 7, then add 5 to the result.
The key to interpeting the phrase correctly is to look at the whole phrase "product of 18 and 7 plus 5". The convention is that the phrase "product of ?1 and ?2" means to multiply ?1 by ?2. In this case, ?1 is just a number, 18. But in the ?2 slot is the phrase "7 plus 5".
The convention is to execute the inner phrase before the outer one. Thus, the steps are:
1. Add 7 to 5, for 12.
2. Multiply 18 times 12, for 216.
If your daughter is given the problem is the shorthand of mathematics, it would be "what is 18*(7+5)". To evaluate this expression, you still work from inner to outer: add 7 and 5 before multiplying by 18.
That is the key to much mathematical manipulation: work from the innermost expression out.
George