Answer:
3:4 and 15:20
Step-by-step explanation:
30: 40 divided by 10 = 3:4
30:40 divided by 2 = 15:20
To calculate the GCF, you need to list all the prime numbers that will go into each number listed
12: 2, 2, 3
60: 2, 2, 3 5
68: 2,2,17
Now you circle the numbers that are the same in each.
GCF: 2, 2
Multiply these numbers to find the GCF: 4
Answer:
3 years 8 month
Step-by-step explanation:
Given 7 years 6 months - 3 years 10 months
Step 1: Firstly we should subtract months from months then after from year to year.
Step 2: 6 months is less than 10 months so we have to borrow 1 year and add it to the months.
Step 3: Adding 1 year to 6 months we get 18 months.
Step 4: Now we have to subtract 3 years 10 months from 6 years 18 months.

Step 5: After subtracting we get 3 years 8 months.
Thus the answer is 3 years 8 months.
Answer:
Commutative Property
Step-by-step explanation:
The word "commutative" comes from "commute" or "move around", so the Commutative Property is the one that refers to moving stuff around. For addition, the rule is "a + b = b + a"; in numbers, this means 2 + 3 = 3 + 2. For multiplication, the rule is "ab = ba"; in numbers, this means 2×3 = 3×2.