SOLUTION: Which number is missing from this sequence? 75 15 ? 5 15 3 13

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Question 1176631: Which number is missing from this sequence?
75 15 ? 5 15 3 13

Found 2 solutions by MathLover1, greenestamps:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

Which number is missing from this sequence?
75 15 ? 5 15 3 13
observe 5 15 3 13, what is a pathern
5%2B10=15
15%2F5=3............so, first divide by+5
3%2B10=13.........then add 10
then before 5 must be a number which divided by 5 gives us 5, and that is 25
Divide the first number by 5 to get the second number.
75%2F5=+15
Add 10 to the second number to get the third number.
15+%2B+10+=+25
Divide the third number by 5 to get the fourth number
25%2F5=5
Add 10 to the fourth number to get the fifth number
5%2B10=15
Divide the fifth number by 5 to get the sixt number
15%2F5=3
Add 10 to the sixt number to get the seventh number
3%2B10+=13
answer: missing number from this sequence is highlight%2825%29

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


The question is impossible to answer; any number there would make a valid sequence.

Presumably the author of the problem had a particular pattern in mind which leads to a specific missing number. But there are almost certainly very different patterns that fit the given numbers and yield a very different missing number.

So the ONLY way to find the RIGHT answer to ANY problem like this is to ask the author of the problem what the answer is.

Therefore, math can't solve this problem; only mind reading can.

Spend as much (or as little) time as you want looking at the problem to see if you can find a logical pattern that produces an answer for the missing number. But realize while you are doing that that any answer you come up with might not be "right".