Among the odd numbers 1.3.5.697 and 699, how many times does the number 5 appear?

It's 5:00
(695-5)/10+1=70
The number ten is five
seven
Hundred:
ten
The number five appears 87 times

Starting from 3, the next number in turn is the previous number plus 3 to get the sequence 3, 6, 9, 12, 15. Is the number 1995 in this row odd or even?

.
The first number is odd and the second is even
And then we found out
The odd number is odd
The even number is even
1995 is an odd number, so the number 1995 is an odd number

If a sequence has 2n + 1 terms, then how many terms are odd and even?

The odd term is one more than the even term
So the odd term is (2n + 1 + 1) / 2 = n + 1
The even term is (2n + 1-1) / 2 = n

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