A percent is that number over 100. Thus 87% can be rewritten as the fraction 87/100. If this is worked out as a division, it can be converted to the decimal 0.87.

Just observe the meaning of the word percent. Per cent. This means per hundred. So 87 percent means 87/100. Now 87 percent of 105 is 87/100 times 105. ie 87 x 105 / 100 = You can finish the simplification.