Answer:
14, 28, 42, 56, and 70 are the first 5 common multiples of 14
20, 40, 60, 80, and 100 are the first 4 common multiples of 20
Step-by-step explanation:
Mean of the origibal set = 20
No. of terms = 10
Sum = Mean x No. of terms
= 20 x 10 = 200
The sum of additional numbers to make the new set of observstion is 4 + 8 + 12...... + 40 = 220
New Sum = 200 + 220 = 420
The no of terms stay the same
New Mean = New Sum/ N
= 420/10
= 42
Its 18 because you would divide 54 bu 3
The original expression is given by:

The correct way to rewrite the expression is given by:

For this, we use two properties:
Associative property:
The way of grouping the factors does not change the result of the multiplication:
Commutative property:
The order of the factors does not vary the product:
4(5)=20
5(5)=25
4 groups of 6th grader
5 groups of 7th graders