If ${{2}^{x+y}}=16$ and ${{4}^{x-y}}=\frac{1}{32}$ , find the values of x and y 

Evaluate ${{\left( \frac{6}{0.32}\div \frac{2}{0.084} \right)}^{-1}}$ correct to 1 decimal place

The weight of a day-old chick was measured to be 0.21g. If the actual weight of the chick is 0.18g, what was the percentage error in the measurement?

The angles of a polygon are given by 2x, 5x, x and 4x respectively. The value of x is

If S = (4t + 3)(t - 2), find ds/dt when t = 5 secs.

Find the value of $\frac{{{(0.5436)}^{3}}}{0.017\times 0.219}$ to 3 significant

Simplify ${{81}^{\tfrac{-3}{4}}}\times {{25}^{\tfrac{1}{2}}}\times {{243}^{\tfrac{2}{5}}}$

The simple interest on ₦8550 for 3 years at x% per annum is ₦4890. Calculate the value of x to the nearest whole number.

Tade bought 200 mangoes at 4 for ₦2.50. 30 out of the mangoes got spoilt and the remaining were sold at 2 for ₦2.40. Find the percentage profit or loss.

If p varies inversely as the square root of q, where p = 3 and q = 16, find the value of q when p = 4.