Posted by Jeffrey on Sunday, April 24, 2011 at 5:12pm.
In a bag there are 7 red tiles, 3 blue tiles, and 2 purple tiles. How many and what color tiles would you have to add to the bag so that the probability of picking red is 1/3?

Probability as a Fraction  bobpursley, Sunday, April 24, 2011 at 5:14pm
you want red to be 1/3, you have 7 to choose from, so you want probability to be 7/21. YOu have 12, how many more non red tiles would you add to make 21?

Probability as a Fraction  Damon, Sunday, April 24, 2011 at 5:17pm
12 in bag now
7/12 are red which is more than 1/3
Say we add x blue tiles
then
7/(12+x) = 1/3
12 + x = 21
x = 9
so add 9 blue tiles for example
check
7 red
12 blue
2 purple
that is 21 total
7/21 = 1/3 check
Answer This Question
Related Questions
 grade 7 mathematics  A bag contains 14 green tiles, 10 red tiles, and 16 blue ...
 Maths  Mary has 6262 square blue tiles and a number of square red tiles. All ...
 !!MATH!!  A decroative floor pattern has one red square tile surrounded by 12 ...
 math  TILING A decroative floor pattern has one red square tile surrounded by ...
 Math accelerated  A decorative floor pattern has 1red square tile surrounded by...
 Probability/Stas  There are 20 red yellow and green tiles in a bag. 1/2 of the ...
 math  susan is buying three different colors of tiles for her kicthen floor. ...
 math (4th grade)  june made a DESIGN with 6 equal tiles.One tile is yellow, 2 ...
 math  june made a design with 6 equal tiles.One tile is yellow, 2 tiles are ...
 8th grade Math  Khalid uses Penelope’s bag of letter tiles to create a ...
More Related Questions