Answer:
let x be the total amount of gallons he bought
$16.80÷$1.40 = x
16.80÷1.40=12
x=12
Step-by-step explanation:
Step-by-step explanation:
You can use the unituary method in this one
First card:
$25/750 min
divide both sides by 750 to figure out how many $ per min the calling card would be
25/750=0.033333333333333333333333333333333333333
750/750=1
the first card costs $0.03333333(going on)/min
Second card
$40/1,300 min
Divide both sides by 1,300
40/1300=0.03076923
1300/1300=1
Second card costs $0.03076923/min
$0.03076923<$0.03333333(going on)
therefore the second card is the better deal
Yes, you need to make the denominators the same. 2/3 becomes 8/12. So now you add 7/12 and 8/12, getting 15/12. But you're not done you need to simplify 15/12. The answer is 1 1/4.
N+d=34
.05n+.10d=2.60
Solve by substitution
n=34-d
.05(34-d)+.10d=2.60
1.7-.05d+.10d=2.60
.05d=.90
d=18 dimes
18+n=34
n=16 nickles
