Of the candidates who sat for an International Mathematics examination, 18% of the candidates obtained grade A, 38% obtained grade B and the rest obtained grade C. Given that 77 candidates obtained grade C, find the total number of candidates who sat for the examination!

Alvin bought a limited edition anime figure and sold it to Ray at 180% of the price of the toy. If Ray paid $900 for the toy, how much did Alvin pay for the toy?

A shopkeeper mixes 30 kg of Brand A tea which is cost $32 per kg with 20 kg of brand B tea which costs $35 per kg. He sells the mixture at $40 per kg. Find his profit or loss as a percentage of his cost!

Given that x is 30% greater than p and y is 60% greater than q. By how many percent is xy greater than pq?

Iskander sells a camera to Ming and makes a profit of 15%. Ming then sells the same camera to Ryan for $414 at a loss of 10%. Find the original price of the camera!

Mr Ong bought some peaches for $294. 16 of the peaches are rotten. He sold all the other good peaches at 40% increase in the cost price and made a profit of $84, How many peaches did he buy?

A Mathematics Club consists of 40 members. 70% of the members are girls. After some members joined the club, 60% of the members are girls. If the new members consist of 6 more boy than girls, how many members in total are boys?

An educational book salesman is paid a basic salary of $520 per month plus a commission of 25% of total sales made during that month. If the books he sold for a particular month is $5264, what is his total income for that month?

John intends to make a new fence for his garden. He buys 5 wooden panel at $25 each, 6 wooden posts at 12$ each, 1 drill bit at $10, 12 bolts which cost $15 for every 6 bolts and 300 g of nails which costs $10 per kg. Find the total amount he has to pay given that he is allowed a discount of 10% and a goods tax of 15% on the amount after the discount!