A bag contains 90 balls. The ratio of the colors red to white to blue is 1:2:3 calculate the probability of choosing (a) a red ball (b) not a red ball (c) a white or red ball (d) how many balls of each color are there?
Answers
Answer:
P(a) = 1/6
P(b) = 1 - 1/6= 5/6
P(c) = 1/2
d) Red ball = 15
White ball = 30
Blue ball = 45
Step-by-step explanation:
Total balls = 90
Let the ratio be x, so x+2x+3x=90
6x=90
x=90/6=15
d) balls of red color= x = 15
balls of white color = 2x = 30
balls of blue color = 3x = 45
P(a) = Total no. of red balls/Total balls
= 15/90 = 1/6
P(b) = Total balls excluding red ball/Total balls
= (90-15)/90 = 75/90 =5/6
P(c) = Total no. of white and red balls/Total balls
= (15+ 30)/90 = 45/90 = 1/2
Answer:
(a) a red ball = 1/6
(b) not a red ball = 5/6
(c) a white or a red ball = 3/6
(d) there are 15 red balls , 30 white balls , 45 blue balls
Step-by-step explanation:
total balls in ratio = 1+2+3 = 6
therefore,
(a) probability of picking a red ball is
ratio of red ball 1
_____________________ = ____.
ratio of total balls 6
(b) probability of picking a ball not red is
ratio of white and blue ball 5
______________________________= ____
total ratio 6
(c) probability of a white or a red ball is
ratio of white and red ball 3 1
_____________________________= ____= ___
total ratio 6 3
(d) for this u can follow the long method and calculate it one by one like,
90 x 1/6.....
90 x 2/6... and so on .
or u can do it in a shortcut by just keep adding 1 to each ratio and add them up until their sum is 90.
example, 1+2+3 = 6
so by adding one to each
2+3+4 = 9
so we can just multiply the whole thing by 10
(2+3+4 = 9) x 10 = 20 + 30 + 40 = 90.