.
how many numbers between 100 and 300 are divisible by 13 ?
~~~~~~~~~~~~~~~~~~~~~~~~~~
First such a number is 104. <<<---=== To find it, first divide
= 7.69; then multiply 13*8 = 104.
Last such a number is 299. <<<---=== To find it, first divide
= 23.08; then multiply 13*23 = 299.
Between 104 and 299, there are
= 15 intervals of the equal length of 13 units in the number line.
Hence, the number under the question is 15+1 = 16.
Answer. 16 numbers.