Answer:
There are 142 whole numbers less than 1000 and divisible by 7.
Explanation:
The multiples of 7 form an arithmetic sequence like shown:
7, 14, 21, ...
The last term of this sequence can be found by dividing 1000/7=142.9 and rounding down to the previous integer: 142*7= 994.
Thus, the sequence has:
a1=7, r=7, an=994. We need to find n and we'll do that by using the general term formula:

And solving for n:


n = 142
There are 142 whole numbers less than 1000 and divisible by 7.