Answer:
The sum of all numbers between 1 and 100 that are divisible by 4 or 7 can be found by using the concept of multiples. First, let's find all the multiples of 4 between 1 and 100. These are 4, 8, 12, 16, ..., 96. To find the number of multiples of 4 between 1 and 100, we can divide 100 by 4 and round down to the nearest whole number. That gives us 25. So, we have 25 multiples of 4 between 1 and 100.
Next, let's find all the multiples of 7 between 1 and 100. These are 7, 14, 21, 28, ..., 98. To find the number of multiples of 7 between 1 and 100, we can divide 100 by 7 and round down to the nearest whole number. That gives us 14. So, we have 14 multiples of 7 between 1 and 100.
Now we need to add up all the multiples of 4 and 7, but we have to make sure not to count any number twice, since some numbers may be divisible by both 4 and 7. For example, 28 is divisible by both 4 and 7. To avoid double counting, we need to find the multiples of 4 * 7 = 28. These are 28, 56, 84. There are 3 multiples of 28 between 1 and 100. So, we subtract these 3 numbers from the sum of all multiples of 4 and 7.
Finally, the sum of all numbers between 1 and 100 that are divisible by 4 or 7 is:
(4 + 8 + 12 + ... + 96) + (7 + 14 + 21 + ... + 98) - (28 + 56 + 84)
= (4 * 25) + (7 * 14) - (28 * 3)
= 100 + 98 - 84
= 114
So, the sum of all numbers between 1 and 100 that are divisible by 4 or 7 is 114.