Answer is 10(2k+5)

-----------------------------------

Work Shown:

20k+50 = 10*2k + 10*5
20k+50 = 10(2k+5)

Note how we can distribute the 10 back in to check our work
10(2k+5) = 10(2k)+10(5) = 20k+50
so that confirms we have the right answer

Another thing to notice is that 10 is the largest factor that we can pull out of 20k and 50. The value 10 is the GCF (greatest common factor) of 20 and 50.

4 0

3 years ago

A boy has only dimes and quarters in his piggy bank. if he has 70 coins worth 12 dollars and 40 cents altogether, how many quart

dlinn [17]

Let us bear in mind the equivalent value of these coins:

One dime = $0.10

One quarter = $0.25

Let x = number of dimes

y = number of quarters

Since the boy has 70 coins in total, we can say that:

x + y = 70 (can be written as x = 70 – y)

Since the boy has a total of $12.40, we can say that:

0.10x + 0.25y = 12.40

To solve this problem, we need to solve this system of equation. We have to substitute the value of x as written in the first equation (x = 70 –y)

0.10(70 – y) + 0.25y = 12.40

7 – 0.10y + 0.25y = 12.40

0.15y = 5.40

y = 36

X = 70 – 36

X = 34

Therefore, the boys has 34 dimes and 36 quarters. To check our answer, we just have to check if his money would total $12.40.

34 dimes = $3.40

36 dimes = $9.00

Total $12.40

7 0

3 years ago

Read 2 more answers