In a race of 200 meters, B can gives a start of 10 meters to A, and C can gives a start of 20 meters to B. The starts that C can gives to A, in the same race is:

According to question,When B runs 200 m meters, A runs 190 meters;Hence, when B runs 180 meters, A runs =$$\frac{{190 \times 180}}{{200}}$$   = 171 meters;When C runs 200m, B runs 180 meters.Hence, C will give a start to A by = 200 - 171= 29 meters