A motor racing circuit has the length of 5 5/6 milesa straight section of the circuit has the length 1 1/4 mileswhat fraction of the circuit is the straight section?

The straight section is 3/14 of the total circuit. This is mostly a problem of adjusting fractions to have common denominators. The fraction of the total circuit is ( length of straight section ) / ( length of total racing circuit ) = ( 1 1/4 ) / ( 5 5/6 ) first, convert the integer parts to a fractions with the same denominator as the fractional part: = ( (1x4)/4 + 1/4 ) / ( (5x6 / 6) + 5/6 ) combine the fractions to make a single fraction in numerator & denominator: = ( 4/4 + 1/4 ) / ( 30/6 + 5/6 ) = ( 5/4) / ( 35/6 ) the division by 35/6 can be done by instead multiplying by the inverse of 35/6: = 5/4 x 6/35 which is done by multiplying the numerators and denominators, and then simplifying by factoring out common divisors from top and bottom: = ( 5 x 6 ) / ( 4 x 35 ) = 30 /140 = 6 / 28 = 3/14