Let X be the smallest positive integer such that 28 and 42 are factors of 678 - X, so the value of X is:
Pick.
A) 28	B) 48	C) 6	D) 62	E) 34
You can simply check which of the possible values for X will make 678-X divisible by 28 and 42 simultaneously.   The only possible value is X = 6 (because   678 - 6= 
<gadget id="calculator">  678 - 6</gadget>
<output>672</output>
672= 28*24 = 42*16).   Answer 6
<result>C</result>
Let X be the smallest positive integer such that 28 and 42 are factors of 678 - X, so the value of X is: