One quarter of Steve's baseball cards are from his dad's collection. Another 0.2 are from his uncle, and 0.5 are from his brother. The rest are from Steve's cousin. Thirty of the cards from his cousin are National League players; the other half are American League. How many cards are in his collection?
3 answers
Uh... I'm guessing that .2 means 20%? Because you can't have .2 of a card? But then the total cards you have sums to over 100% and welp.
total collection ---- x
from dad --- x/4
from uncle --- x/5 ---> (.2)x = (2/10)x = x/5
from brother --- x/2
leaving : x -x/4 - x/5 - x/2 = x/20
so from cousin = x/20
so (1/3)(x/20) = 30
x = 1800
Steve has 1800 cards
check:
from dad = 1800/4 = 450
from uncle = .2(1800) = 360
from brother = (1/2)(1800) = 900
Total of that = 1710
so 1800-1710 or 90 are from cousin
(1/3) of those are NL players
(1/3)(90) = 30 , as it said in the question.
from dad --- x/4
from uncle --- x/5 ---> (.2)x = (2/10)x = x/5
from brother --- x/2
leaving : x -x/4 - x/5 - x/2 = x/20
so from cousin = x/20
so (1/3)(x/20) = 30
x = 1800
Steve has 1800 cards
check:
from dad = 1800/4 = 450
from uncle = .2(1800) = 360
from brother = (1/2)(1800) = 900
Total of that = 1710
so 1800-1710 or 90 are from cousin
(1/3) of those are NL players
(1/3)(90) = 30 , as it said in the question.
I misread
"Thirty of the cards from his cousin are National League players"
as
one third of the cards from his cousin are NL players
"Thirty of the cards from his cousin are National League players"
as
one third of the cards from his cousin are NL players
1 answer