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