What is the smallest four-digit number that can be

Solution

We know the smallest four digit number = 1000 LCM of 20, 24 and 36 = 360 Now, when we divide the smallest four digit number i.e. 1000 by 360, then we get the 280 as remainder. So, the smallest four digit number which is exactly divisible by 20, 24 and 36 = {1000 + (360 – 280)} = 1080 Alternate Solution Since, the number is divisible by 20, 24 and 36 this means it is a multiple of 4 Out of given options, only 1000 and 1080 are multiple of 4 but 1000 is not a multiple of 24 and 36 Therefore, required number = 1080