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ms.hi
Estimate 51% of 162. b) Use mental math to calculate 51% of 162.
51% is close to 50%, or half Half of 162 is 81. Since 51% is just 1% more than half, and 1% of 162 is approx 2, I'd say approximately 83.
51% is 50% + 1%, so it is half + 1%. Half of 162 is 81. 1% of 162 is 1,62. 81+1,62=82,62. Done!