In the diagram, POS and ROT are straight lines, OPQR is a parallelogram. |OS| = |OT| and ∠OST = 50°. Calculate ∠OPQ.

Simplify \(\left(\frac{16}{81}\right)^{-\frac{3}{4}}\times \sqrt{\frac{100}{81}}\)

Express \(\frac{7}{19}\) as a percentage, correct to one decimal place

If \(104_x = 68\), find the value of x

Which of the following numbers is perfect cube?

What fraction must be subtracted from the sum of \(2\frac{1}{6}\) and \(2\frac{7}{12}\) to give \(3\frac{1}{4}\)?

Find the missing number in the addition of the following numbers, in base seven \(\begin{matrix} 4 & 3 & 2 & 1\\ 1 & 2 & 3 & 4\\ * & * & * & *\\ 1&2&3&4&1 \e...

simplify \(\frac{10}{\sqrt{32}}\)

Express 398753 correct to three significant figures