the greatest number which on dividing 1642 and 1856 leaves remainders 6 and 4 respectively , is :
"explanation : required number = h . c . f . of ( 1642 - 6 ) and ( 1856 - 4 ) = h . c . f . of 1636 and 1852 = 4 . answer : d"
gcd(subtract(1856, 4), subtract(1642, 6))