What are some strategies you can use to mentally solve this expression?

What is an example of a calculation using one operation (addition, subtraction, multiplication, or division) that cannot be easily computed mentally? What are some strategies you can use to mentally solve this expression? Which mathematical properties does your strategy require?

square roots are alot like women. if they’re…

oh…wait…just one operation. let’s see…

i have a difficult time squaring (multiplying) a million by a million. the strategy is to use exponents but when i put all those zeroes in the answer…it’s difficult to comprehend mentally.

Also…any situation involving a formula, ‘work’ for example. how to figure work. the strategy: 1) know the formula (i.e. work = force * distance [physics] or work = rate * time [business]) and 2) use dimensional analysis to solve and check the answer (i.e. work units might be letters so the rate would be letters per time and the time units = minutes)

last thought…never use an answer without reflecting upon the feasibility of it. i mean…does it really make sense that a baseball pitcher hurls a slider at 217 mph? probably not.

Well…

Good luck.