'In a certain factory there are five workers `A ,|| B ,|| C ,|| D`and `E`. `A`can complete a work

"In a
certain factory there are five workers `A ,\\ B ,\\ C ,\\ D`
and `E`
. `A`
can
complete a work in 4 minutes, `B`
in 5
minutes, `C`
in 6
minutes, `D`
in 10
minutes and `E`
in 12
minutes. The average number of units of work completed per worker per minute
will be
(a)
0.16 (b) 0.172 (c) 0.80 (d) 0.87"

complete