ACT Math 5.5 Pre-Algebra
ACT Math: Pre-Algebra Drill 5, Problem 5. How many red cards must be added so that the proportion of red cards is one half?
|Foreign Language||Arabic Subtitled|
Ratio, proportion, and percent
|Product Type||ACT Math|
|Ratios, Percentages, and Proportions||Proportions|
So... we're not dealing with a standard deck of playing cards. Kind of hard to play
"Go Fish" with only one eight.
Okay, so here's a scale: 23 cards on the left -- red ones; 30 cards on the right -- black ones.
To get the red cards to be half of the total, or equal to the black cards...
...we need to have just as many of them as we have black cards.
We can just add 7 of 'em, and then we'll have 30 of each.
And that's all there is to it. Answer: D.
As in, "Deck of Card."