18 × 35 I 90 54 I 630

Therefore, there are 630 filters in the supply room.

Division is the process of finding how many times one number (called the divisor) is contained in another number (called the dividend). The result is the quotient, and any amount left over is called the remainder.

quotient l d i v i s o r dividend

Example: 218 landing gear bolts need to be divided between 7 aircraft. How many bolts will each aircraft receive?

31 7 218 − 2 1

8 − 7

1

In this case, there are 31 bolts for each of the seven aircraft with one extra remaining.

A fraction is a number written in the form N⁄D where N is called the numerator and D is called the denominator. The fraction bar between the numerator and denominator shows that division is taking place.

Some exa mples of fractions a r e: 17, 2, 5 18 3 8

The denominator of a fraction cannot be a zero. For example, the fraction 2⁄0 is not allowed, because dividing by zero is undefined.

An improper fraction is a fraction in which the numerator is equal to or larger than the denominator. For example, 4⁄4 or 15⁄8 are examples of improper fractions.

To add or subtract fractions, they must have a common denominator. In math, the least common denominator (LCD) is generally used. One way to find the LCD is to list the multiples of each denominator and then choose the smallest number that they all have in common (can be divided by).

Multiples of 5 are: 5, 10, 15, 20, 25, and so on. Multiples of 10 are: 10, 20, 30, 40, and so on. Notice that 10, 20, and 30 are in both lists, but 10 is the smallest or LCD. The advantage of finding the LCD is that the final answer should be in the simplest form.