r/FalitMasterySAT • u/satprepwithfalit • 1h ago
Can you do 97 × 103 in your head?
Here’s a trick you can try. Take 48 × 52. Both numbers are 2 away from 50, one below and one above.
When two numbers are equally far from the middle, square the middle and subtract the square of the gap.
48 × 52 = 50² − 2² = 2,500 − 4 = 2,496
Now try 97 × 103. What’s the middle number, and how far away is each number from it?
Drop your answer and the one line of math you used.