You mean the math is intentionally "scaled up"? Or that the math is just easier & there is no effort made to rescale it? Given that these scores are used for comparison so often, you'd think they would normalize the scores so that a 700 means the same thing on both sections.
For what it's worth, this is a trend on other standardized tests as well (including the SAT).
For what it's worth, this is a trend on other standardized tests as well (including the SAT).