Fire load $($MJ$/$m$2)$ is the heat energy that could be released per square meter of floor area by combustion of contents and the structure itself. The following cumulative percentages are for fire loads in a sample of $388$ rooms:

Value $0150300450600750900$

Cumulative $\%019\mathrm{.}137\mathrm{.}662\mathrm{.}176\mathrm{.}986\mathrm{.}593\mathrm{.}5$

Value $1050120013501500165018001950$

Cumulative $\%95\mathrm{.}297\mathrm{.}798\mathrm{.}099\mathrm{.}599\mathrm{.}699\mathrm{.}8100\mathrm{.}0($b$)$ What proportion of fire loads are less than $600?$ At least $1200?($Round your answers to three decimal places.$)$

less than $600$

at least $1200$