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I once met six siblings whose ages are 6 consecutive whole numbers. i asked each of them the question how old is your oldest sibling. which of the following could not be the sum of their answers.

A. 95
B. 125
C. 167
D. 205
E. 233

User Monroe Thomas
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2 Answers

12 votes
12 votes

Final answer:

To find the sum of the ages of the six siblings, we can use the formula for the sum of an arithmetic sequence. We check which of the given options cannot be obtained by plugging in different values of 'x' and calculating the sum.

Step-by-step explanation:

To find the sum of the ages of the six siblings, we can use the formula for the sum of an arithmetic sequence:

Sum = (n/2)(2a + (n-1)d)

In this case, 'n' is 6 (the number of terms), 'a' is the first term, and 'd' is the common difference between consecutive terms. Since the ages are consecutive whole numbers, 'd' is equal to 1. We can choose any number for 'a'. Let's assume the first sibling's age is 'x', so the ages of the six siblings are 'x', 'x+1', 'x+2', 'x+3', 'x+4', and 'x+5'.

Now we can substitute these values into the formula and calculate the possible sums:

Sum = (6/2)(2x + (6-1)1) = 3(2x + 5) = 6x + 15

We check which of the given options cannot be obtained by plugging in different values of 'x' and calculating the sum. The answer is Option A. 95, as it cannot be obtained by any value of 'x'.

User Daycaster
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16 votes
16 votes

Answer:

Step-by-step explanation:

I once met six siblings whose ages are 6 consecutive whole numbers. i asked each of-example-1
User Eugene Pakhomov
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