Careless SAT Math Error #1: Answering the wrong question
The SAT Math section is notorious for asking for “weird” information – instead of the value of “X,” you may be asked for the value of “3X.” A word problem might be written in terms of “hours,” but the question asks for an answer in “minutes.” This sort of deception happens all over the math section, so be very careful about answering the question that is asked. It is very helpful to underline or box the part of the question that contains the specific value you have been asked to find, as a reminder to yourself to answer the correct question.
Careless SAT Math Error #2: Prime Number Confusion
Many SAT prep students are surprised to learn that the number 1 is not actually a prime number. The reasons for this are confusing, even to me, so all you have to do is focus on remembering that 1 is NOT prime, and the lowest prime number is “2” (2 is also the ONLY even prime number).
A good number of SAT math questions depend on knowing the first few prime numbers, so don’t make this careless error – remember that “2 is the smallest prime number!”
Careless SAT Math Error #3: Not noticing a special triangle
The SAT loves triangles. It is also very sneaky about hiding special right triangles in plain sight. If you’re working on a geometry problem and you see any angle that measures 30, 45, 60, or 90 degrees, start looking for a special right triangle right away.
Remember from math class that the two special right triangles are 45-45-90 and 30-60-90. When you come across one of these triangles, you can easily figure out the side lengths of the triangle using basic formulas. Make sure to brush up on your special right triangles to conquer the SAT and avoid overlooking them by mistake.
Careless SAT Math Error #4: Losing a negative sign
I see this careless mistake ALL the time in my SAT prep tutoring lessons, and it breaks my heart! You figure out an incredibly tough word problem, set it up, do the calculations, get an answer.. and then be totally wrong, because you lost a negative sign somewhere along the way.
It’s really easy to make this mistake, because you’re in a hurry and you probably aren’t using your best math handwriting. However, you simply cannot give up easy points because you forgot a negative. Slow down, and make to be extra-careful any time positive and negative numbers are involved.
Careless SAT Math Error #5: Not checking your work
This careless error ties the other 4 together. If you have any time left after you’ve done all the problems you know how to do in a section, start checking your work from scratch, beginning with the hardest or most complicated problem and working backwards towards the easier problems. If there was any math question that you felt uncertain about or think you may have made a mistake on, start there.
Most SAT prep students should NOT be attempting to answer every question in the math sections, and instead should focus on only answering questions they know how to do. That leaves a little extra time at the end of the section to check your work and look for any other careless mistakes. Read more here.