$9999 + 8888 + 777 + ? = 19700$

$P, Q$ and $R$ scored $581$ runs such that $4$ times $P$'s runs are equal to $5$ times $Q$'s runs,which are equal to $7$ times $R$'s runs. Find the difference between $P$'s runs and $R$'s runs.

The sum of a non-$zero$ number and twice its reciprocal is $\frac{33}{4}$. Find the number.

How many positive factors of $36$ are there?

$38 \%$ of $? = 3596 - 632$

The product of two natural numbers is $17$. Then the sum of the reciprocals of their squares is