What's the answer to 14? Math?

d: number of dimes → the value is: 5 cents → i.e. $0.05

x: number of quarters → the value is: 25 cents → i.e. $0.25


Fred has 20 coins:

d + x = 20

d = 20 - x ← answer 13)


The value is:

= (d * 0.05) + (x * 0.25)

= 0.05d + 0.25x → recall: d = 20 - x

= 0.05.(20 - x) + 0.25x

= 1 - 0.05x + 0.25x

= 1 + 0.20x ← answer 14)...Show more

a)
Let x be the number of quarters and y be the number of dimes
Then, x+y=20
y = 20-x

b)
0.25x+0.10y dollars...Show more

Fred has 20 coins.
Some of his coins are quarters and some are dimes.
If Fred has x quarters, find the following:
a.
Write an algebraic expression for the number of dimes he has.
y = 20 - x
b.
Write an algebraic expression for the value of his coins.
25x + 10(20 - x)...Show more