Find the product :

34.2 x 1.86

First we multiply 342 by 186

$\begin{matrix} & & 3 & 4 & 2 \ \times & & 1 & 8 & 6 \ \hline & 2 & 0 & 5 & 2 \ 2 & 7 & 3 & 6 & \times \ 3 & 4 & 2 & \times & \times \ \hline \bold{6} & \bold{3} & \bold{6} & \bold{1} & \bold{2} \end{matrix}$

Clearly, 342 × 186 = 63612

Sum of decimal places in given decimals = (1 + 2) = 3

So, the product contains 3 places of decimal

∴ 34.2 × 1.86 = 63.612