SOLUTION: the smallest fraction which, when added to 2/5*15/21*7/10*3/8 given a whole number is: 36/37,37/40 how to solve it?

Factor all numbers into primes:



Cancel a pair of 2's






Cancel a pair of 3's





Cancel a pair of 5's





Cancel a pair of 7's





So that becomes:





The next whole number to that is 1

We subtract that from 1 to find out what we must 
add to  to get the next whole number, 1.



Write 1 as 



Answer: 

Edwin