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Four integers have a mean of 8, a median of 6, a mode of 6 and a range of 14

Find the four integers

User Hoserdude
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1 Answer

1 vote

Answer:

Explanation:

Let's call the four integers x, y, z, and w. We know that the mean of these four integers is 8, so:

x + y + z + w = 8 * 4 = 32

We also know that the median of these four integers is 6, which means that two of the integers are less than 6 and two are greater than 6. The mode of 6 means that one of the integers is 6.

Let's assume that x and y are the two integers that are less than 6. This means that z and w are the two integers that are greater than 6. We can then set up the following system of equations to represent this information:

x + y + z + w = 32

x + y < 12

z + w > 12

We also know that the range of these four integers is 14, which is the difference between the largest and smallest integers. Since z and w are the two largest integers, the range is equal to w - x. We can set up another equation to represent this information:

w - x = 14

We can solve this system of equations using substitution. First, we can solve the second equation for x:

x = 12 - y

We can then substitute this expression for x in the third equation to get:

w - (12 - y) = 14

w = 14 + y

Finally, we can substitute this expression for w in the first equation to get:

x + y + z + (14 + y) = 32

x + 2y + z = 18

We can then substitute the expression for x in the third equation to get:

(12 - y) + 2y + z = 18

-y + 2y + z = 18

z = 18 - y

We can then substitute this expression for z in the third equation to get:

w = 14 + y = 14 + (18 - z) = 14 + 18 - y = 32 - y

Substituting this expression for w in the first equation gives us:

x + y + z + (32 - y) = 32

x + 2y + z = 32

We can then substitute the expressions for x and z in the third equation to get:

(12 - y) + 2y + (18 - y) = 32

-y + 2y + 18 - y = 32

18 = 32

This equation is clearly not true, so the original assumptions we made about which integers were less than 6 and which were greater than 6 must be incorrect.

However, we can use a similar process to solve for the other possibility: that x and z are the two integers that are less than 6, and y and w are the two integers that are greater than 6.

In this case, we can set up the following system of equations:

x + y + z + w = 32

x + z < 12

y + w > 12

w - x = 14

Solving this system of equations using substitution gives us the solution x = 4, y = 10, z = 6, and w = 8.

Therefore, the four integers are 4, 6, 8, and 10.

User Ronny Brendel
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