Add 60 Seconds for Brain Power - Subtraction Lite Free

******************************* Promotion: Free for One Day Only ******************************* 60 seconds of speed math to boost your brain power. The rules are simple: determine if the equation is right or wrong. If right, tap the "checkmark" button. If wrong, tap the "X" button. Players have 60 seconds to get as many questions right as possible. The questions get progressively hard as m…