Can someone show me how to use venn diagrams or a table to solve this problem.
I am having a lot of trouble solving these type of problems
100 people
50 purchase cake
40 purchase muffin
20 purchase both cake and muffin
So how do I know how many dont purchas either
What else do I need to know
Problem attached
using venn diagrams
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I have attached the Venn diag.
Important point to observe in the question.
1. The question says 50 purchase cake mix and 40 purchase muffin mix.
Whenever u see a sentence like above, where the key word "only" is missing, assume that the number is a combo of "only" + "both" (or all 3)
So in this case, 50 includes ppl who bought ONLY cake mix + those who bought cake mix and muffin mix.
With this u can easily plug in the venn diagram.
a) first plugin in the value of 20 in the intersection of cake and muffin,
b) Now subtract 20 from 50 and 40 respectively and plugin to the respective circles.
c). Subtract the total of 3 values from 100. This is the "None" value, which is outside of all circles.
So we can easily find the probability:
30/100 = 3/10
HT Helps
Good luck
Important point to observe in the question.
1. The question says 50 purchase cake mix and 40 purchase muffin mix.
Whenever u see a sentence like above, where the key word "only" is missing, assume that the number is a combo of "only" + "both" (or all 3)
So in this case, 50 includes ppl who bought ONLY cake mix + those who bought cake mix and muffin mix.
With this u can easily plug in the venn diagram.
a) first plugin in the value of 20 in the intersection of cake and muffin,
b) Now subtract 20 from 50 and 40 respectively and plugin to the respective circles.
c). Subtract the total of 3 values from 100. This is the "None" value, which is outside of all circles.
So we can easily find the probability:
30/100 = 3/10
HT Helps
Good luck
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vittalgmat has given a good explanation on solving the problem using Venn Diagram. The other way to solve this question is by using the following equation
Total = A+B+Neither-Both
Total = customer purchasing cake mix + customers purchasing muffin mix + customers purchasing neither cake or muffin mix - customers purchasing both cake and muffin mix
100 = 50 + 40 + N - 20
N = 30
Probability of neither = 30/100 or 3/10
Total = A+B+Neither-Both
Total = customer purchasing cake mix + customers purchasing muffin mix + customers purchasing neither cake or muffin mix - customers purchasing both cake and muffin mix
100 = 50 + 40 + N - 20
N = 30
Probability of neither = 30/100 or 3/10
SACX
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Thank you sooooooo much everyone
except vital gmat who went to the extent of makin a diagram
THANK OU
except vital gmat who went to the extent of makin a diagram
THANK OU
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Is easy
C ake 50
M uffin 40
B oth 20
Total 100
No cake and muffin ?
Remember the formula
C-B + B + M-B + ? = TOTAL
50 – 20 +20 + 40-20 + ? = 100
RESULT:
?= 30
SO THE PROBABILITY IS
PART/ WHOLE ….. 30/100
3/10
THE ANSWER IS C
C ake 50
M uffin 40
B oth 20
Total 100
No cake and muffin ?
Remember the formula
C-B + B + M-B + ? = TOTAL
50 – 20 +20 + 40-20 + ? = 100
RESULT:
?= 30
SO THE PROBABILITY IS
PART/ WHOLE ….. 30/100
3/10
THE ANSWER IS C
LEARNING ENGLIS H