a runs 1 ¾ times as fast as b . if a gives b a start of 84 m , bow far must winning post be so that a and b might reach it at the same time ?
. ratio of the rates of a and b = 7 / 4 : 1 = 7 : 4 . so , in a race of 7 m , a gains 3 m over b . : . 3 m are gained by a in a race of 7 m . : . 84 m are gained by a in a race of ( 7 / 3 x 84 ) m = 196 m . : . winning post must be 196 m away from the starting point . answer is a .
multiply(divide(add(const_4, const_3), const_3), 84)