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MathRevolution
When a certain computer plays 24-point game, each of Δ and @ representative operation of addition, subtraction, multiplication, and division. And each of the symbol has the following probability,

Δ -> +: 0.4 -:0.3×: 0.2 ÷: 0.1
@ -> +:0.6 -: 0.2 ×: 0.1 ÷: 0.1.

What is the probability if the computer calculates (4Δ2)(3@1)=24?

A. 0.28
B. 0.34
C. 0.44
D. 0.64
E. 0.84


* A solution will be posted in two days.

I think Option A should be 0.26. Correct me if am wrong.

Probability of two events getting 24

For the given set {4,2} Set1 and {3,1} Set2 the maximum possible values are
{4,2} Max value = 8 (4 multiplied by 2) and Min Value = 2 (4 divided by 2)
{3,1} Max value = 4 (3 + 1) and Min Value = 2 (3 - 1)

Factors of 24 should be multiple of 8 for less than that based on the above calculation.

based on that we can arrive as below
(4*2)(3*1) = 24
(4+2)(3+1) = 24

Case1: Both SET1 AND SET2 should have the symbol as '*'. Since AND its multiplication. = .1 * .2 = 0.02
Case2: Both SET1 AND SET2 should have the symbol as '+'. Since AND its multiplication. = .6 * .4 = 0.24

Now the chance of getting 24 as outcome for the given sets are --> It should be either CASE1 or CASE2

'OR' in probability is addition. Hence = 0.24 + 0.02 = 0.26

You are perfectly fine in two scenarios, but you are missing out on th ethird scenarioo..
1) (4*2)(3*1)=24
prob=.4*.6=.24

2)(4+2)(3+1)=24..
.2*.1=.02..
and

3) (4*2)(3/1)=24

.2*.1=.02

total= .24+.02+.02=.28..

you have missed out on third scenario..

Since .28 is nearer to .26 chose A :lol: :lol: . Thanks for notifying :D:D Need to pretty carefu.. Thanks again....
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When a certain computer plays 24-point game, each of Δ and @ representative operation of addition, subtraction, multiplication, and division. And each of the symbol has the following probability,

Δ -> +: 0.4 -:0.3×: 0.2 ÷: 0.1
@ -> +:0.6 -: 0.2 ×: 0.1 ÷: 0.1.

What is the probability if the computer calculates (4Δ2)(3@1)=24?

A. 0.28
B. 0.34
C. 0.44
D. 0.64
E. 0.84


-> The number of cases for (4Δ2)(3@1)=24 is
from Δ=× and @=× or ÷, (0.2)(0.1)+(0.2)(0.1)=0.04
and from Δ=+ and @=+, (0.4)(0.6)=0.24, which becomes 0.04+0.24=0.28.
Thus, A is the answer.
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MathRevolution
When a certain computer plays 24-point game, each of Δ and @ representative operation of addition, subtraction, multiplication, and division. And each of the symbol has the following probability,

Δ -> +: 0.4 -:0.3×: 0.2 ÷: 0.1
@ -> +:0.6 -: 0.2 ×: 0.1 ÷: 0.1.

What is the probability if the computer calculates (4Δ2)(3@1)=24?

A. 0.28
B. 0.34
C. 0.44
D. 0.64
E. 0.84


* A solution will be posted in two days.


I did not get the interpretation of symbols. Can anybody please explain me?
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MathRevolution
When a certain computer plays 24-point game, each of Δ and @ representative operation of addition, subtraction, multiplication, and division. And each of the symbol has the following probability,

Δ -> +: 0.4 -:0.3×: 0.2 ÷: 0.1
@ -> +:0.6 -: 0.2 ×: 0.1 ÷: 0.1.

What is the probability if the computer calculates (4Δ2)(3@1)=24?

A. 0.28
B. 0.34
C. 0.44
D. 0.64
E. 0.84


* A solution will be posted in two days.


I did not get the interpretation of symbols. Can anybody please explain me?



--> (4+2)(3+1) or (4*2)(3*1), or (4*2)(3/1)
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MathRevolution
When a certain computer plays 24-point game, each of Δ and @ representative operation of addition, subtraction, multiplication, and division. And each of the symbol has the following probability,

Δ -> +: 0.4 -:0.3×: 0.2 ÷: 0.1
@ -> +:0.6 -: 0.2 ×: 0.1 ÷: 0.1.

What is the probability if the computer calculates (4Δ2)(3@1)=24?

A. 0.28
B. 0.34
C. 0.44
D. 0.64
E. 0.84


* A solution will be posted in two days.
This table worked for me:



0.24 + 0.02 + 0.01 + 0.01 = 0.28

Answer: A
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