There are 7 times as many females as males on the maths course at university. What fraction of the course are male? Give your answer in its simplest form.

Adepartment store purchases screen-printed t-shirts at a cost of $5 per shirt. they mark up the price 150% (making the selling price 250% of the store's purchase price) and put them on the sales floor. every month that a t-shirt doesn't sell, the store reduces the selling price by 25%.

Prove that the sum of two consecutive exponents of the number 5 is divisible by 30.if two consecutive exponents are 5n and 5n + 1, then their sum can be written as 30.

Present age of man is 45 years, 5 years back his age was 4 times age of his son what is present age of his son?