Simplify, correct to three significant figures, ${{(27.63)}^{2}}-{{(12.37)}^{2}}$ 

Express, correct to three significant figures, 0.003597

There are 250 boys and 150 girls in a school. If 60% of the boys and 40% of the girls play football, what percentage of the school plays football?

Express 0.0000407 correct to 2 significant figures

The monthly salary of a man increased from N2,700 to N3,200. Find the percentage increase

The salary of a man was increased in the ratio 40: 47. Calculate the percentage increase in the salary

Correct 0.04945 to two significant figures

A baker used 40% of a 50kg of flour. If $\tfrac{1}{8}$ of the amount used was for cake, how many kilogram of flour was used for the cake? 

If 30% of y is equal to x, what, in terms of x is 30% of 3y

Evaluate (0.13)³ correct to three significant figures.