For either one of the deals, just find what one card equals and times it by how many cards the other equation has.
e.g. 0.35 cents divide by 10 = 0.035. And now, you times it by 12 since the other deal is 12 cards for 40 cents.
0.035 x 12 = 0.48
So, 10 cards for 35 cents is not the better deal.
3
Going up 7 and then down 4 can be represented by 7-4=3
change to improper fractions
42 1/3
(3* 42 +1) /3 = 127/3
1 1/3 = (3*1 +1) /3 = 4/3
127/3 divided by 4/3
copy dot flip
127/3 * 3/4
127/4
31 3/4 miles per hour
He drove 31 3/4 miles in one hour
31 3/4 miles 1 mile
------------ = ------------
1 hours x hour
using cross products
31 3/4 * x =1*1
x = 1/ 127/4 (copy dot flip)
x = 1 * 4/127
x = 4/127
it takes 4/127 of 1 hour (approx .03 hours)
<span>96-2r=6r-112
Add 2r to both sides
96=8r-112
Add 112 to both sides
208=8r
Divide 8 on both sides
Final Answer: 26=r</span>