Grade Six Mathematics
LOWEST COMMON MULTIPLE (L.C.M)
Hello Boys and Girls,
A multiple is a number formed by multiplying it by a natural number. Multiples go on to infinity, that is, they never end and we can list them on, and on and on.
Using a Venn diagram to list and find the LCM
The more multiples you list the more common multiples you will have. However, you can only have one lowest common multiple.
Can you think of another common multiple of 4 and 6?
PRACTICE EXAMPLE 1
To find the LCM, we can use division.
Step 1 – Draw a t-chart as shown below and write both numbers on the right-hand side.
Step 2- Divide the numbers starting with the smallest factor is your divisor. Write your divisor on the left-hand side.
Step 3- Continue to divide until you get 1.
Step 4- Multiply all the numbers on the left-hand side of your chart. (All the divisors used)
Example 1(a)
We can use THE L.C.M to solve problems. L.C.M is used to find the least number of items we want to put into groups or the smallest number that is divisible by another number. Either way, L.C.M. is used in our everyday life.
PRACTICE EXAMPLE 2
A shopkeeper sells candles in packets of 15 and candle stands in packets of 9. What is the least number of candles and candle stands the shopkeeper should buy so that there will be one candle for each candle stand?
Multiples of 15 = 15, 30, 45, 60…
Multiples of 9 = 9, 18, 27, 36, 45…..
Common multiple = 45
L.C.M = 45. Therefore, the least number of candles shopkeeper should buy is 45.
HOMEWORK
Until next week, goodbye Boys and Girls. and candle stands that the 1. Insert the numbers in the correct place on the Venn diagram below. Write two other common multiples of 5 and 6 in the intersection. Using repeated division to find the LCM. 3. Find the lowest number that is divisible by 14 and 28. 4. Kiara baked 30 oatmeal cookies and 48 chocolate chip cookies to package in plastic containers for her friends at school. She wants to divide the cookies into identical containers so that each container has the same number of each kind of cookies. If she wants each container to have the least number of cookies possible, how many plastic containers does she need?
5. Colton has 16 blue marbles and 8 white ones. If he wants to place them in identical groups without any marbles left over, what is the greatest number of groups Colton can make?