A partially dried clay mineral contains `8%`d water. The original sample contained `12%` water and `45%` sillica.
The `%` if sillica in the partially dried sample is nearly:

Options

A. `50%`
B. `49%`
C. `55%`
D. `47%`

Answer

4

Explanation

Let original sample weighs `xx g`
water `=(12)/(100)x, ` silica `=(45)/(100)xxx`
Impurities `=(43)/(100)x`
Partially dried sample weight `y g`
Water `=(8)/(100)y`
Since no evaporational silica `&` impurites. So,
`(45)/(100)x+(43)/(100)x=(92)/(100)yrArrx=(92)/(88)y`
`%` of silica in partially dried sample `((45)/(100)xxx)/(y)xx100=47%`