Question

B) When heated an iron bar expands by 0.2%. If the increase in length is 1 cm,

what is the original length of the bar ? ​

Answer 1

Simple algebra.

When we convert this to an equation we get: 0.2% of something is equal to 1 unit.

So here's the equation:
`0.02x = 1`

After we transpose
`0.02`, the equation become:
`x = (1)/(0.02)`.

Divide
`1` with
`0.02` and you get
`50`.

So the length of the original bar is
`50` cm. :D