Find the least multiple of 7 that leaves the remainder 4 when divided by 6, 9, 15 and 18.

Set up an equation in the form N = LCM × k + 4, where N must also be a multiple of 7.

LCM of 6, 9, 15, and 18 is 90

So, any number that satisfies the condition must be of the form:

N = 90k + 4

where k is an integer. (k = 1, 2, 3 ,4,….)

put k = 4

N = 90 × 4 + 4 = 364

Thus,  The least multiple of 7 that leaves a remainder of 4 when divided by 6, 9, 15, and 18 is 364.