Find the product :

1.1 x 0.1 x 0.11

First we multiply 11 by 1 and then by 11

$\begin{matrix} & 1 & 1 \ \times & & 1 \ \hline & \bold{1} & \bold{1} \end{matrix}$

∴ 11 × 1 = 11

$\begin{matrix} & & 1 & 1 \ \times & & 1 & 1 \ \hline & & 1 & 1 \ & 1 & 1 & \times \ \hline & \bold{1} & \bold{2} & \bold{1} \end{matrix}$

∴ 11 × 1 x 11 = 121

Sum of decimal places in given decimals = (1 + 1 + 2) = 4

So, the product contains 4 places of decimal

∴ 1.1 × 0.1 × 0.11 = 0.0121