Question

Simplify the expression 3/15-2/25=

Answer 1

Since the 2 fract. have diff. denoms., we must find the LCD.

Note that factors of 15 are 3 and 5, and that
factors of 25 are 5 and 5.  The LCD thus includes 5, 3 and 5, and is 75.  Notice that both 15 and 25 divide evenly into 75.

Thus we have
                                                                                                 3*3
15/75 - 6/75, or -9/75.  This must be reduced; the answer is - --------
                                                                                                   3*25

and this reduces further to 3/25 (answer).

Answer 2

45 3
__ / 15 = ___

75 5