Recent research shows that your hunch as a parent is right. There are three reasons why a child may not be able to crack a math problem:
1. Does not know/makes a mistake in the arithmetic
2. Is unable to comprehend the word problem
3. Unable to interpret the word problem numerically
Majority of the cases it was #3 - inability to interpret the word problem numerically -that was identified as the problem. However we spend enormous amount of time & effort on getting them to be really fast and accurate at arithmetic calculations!
How will all the speed and accuracy in the world save your child if she can't interpret which operation to use or worse still understand that math is a language that enables her to interpret the world around her numerically and not the other way round!