Find my weak spots

Today's drill

How To Improve Mental Math

Updated September 25, 2026

Mental arithmetic slows you down. Every sum costs attention, so there is less left for the actual problem.

Do this one today

Estimate first

A rough answer first stops you from trusting a wrong exact one. 18% of 240 is near 20% of 240, so about 48 (exactly 43.2).

Estimate three percentages today before you calculate them.

Also in this one

That one comes with IQ Tester, one a day, aimed at whichever of these is actually yours.

Which one is yours?

Find your weak spots in two minutes, then train them with one short drill a day, picked for you.

Find my weak spots

The other 6

Every problem IQ Tester looks for