in a 400 m race , a covers the distance in 60 seconds and b in 100 second . in this race a beats b by :
"solution distance covered by b in 40 sec . = ( 400 / 100 x 40 ) m = 160 m . ∴ a beats b by 160 metres . answer d"
multiply(divide(400, 100), subtract(100, 60))