Find the number :
85% of 420 + ?% of 1080 = 735

Given,
(85% of 420) + (?% of 1080) = 735
$$ \Rightarrow \left( {\frac{{85 \times 420}}{{100}}} \right) \times \left( {\frac{{(?) \times 1080}}{{40}}} \right)$$       $$= 735$$
$$\eqalign{ & \Rightarrow 357 + \left( {\frac{{(?) \times 1080}}{{100}}} \right) = 735 \cr & \Rightarrow \left( {\frac{{(?) \times 1080}}{{100}}} \right) = \left( {735 - 357} \right) \cr & \Rightarrow \left( {\frac{{(?) \times 1080}}{{100}}} \right) = 378 \cr & \Rightarrow (?) = \frac{{378 \times 100}}{{1080}} \cr & \Rightarrow (?) = 35 \cr} $$