A can give 40 metres start to B and 70 metres to C in a race of one kilometre how many metres starts can B give to C in a race of one kilometre ?

$$\eqalign{ & \,\,\,\,\,{\text{A}}\,\,\,\,\,\,\,\,\,\,\,\,{\text{B}}\,\,\,\,\,\,\,\,\,\,\,{\text{C}} \cr & {\text{1000}}\,\,\,\,\,\,{\text{960}}\,\,\,\,\,\,{\text{930}} \cr} $$
⇒ B can give C a start of 30 metres in a 960 metres race
⇒ 960 units → 30
⇒     1 unit → $$\frac{1}{32}$$
⇒ 1000 units → $$\frac{1000}{32}$$
  = $$31\frac{1}{4}$$ metres