The total resistance of four resistors in parallel with vales of 3,5,20and 50 ohms is how many ohms

1.658 ohms

Hk, was this homework?

Probably, but answer won't help if person doesn't know how it was done.

True...
I hope the instructor requires the work to be shown...
(I did)

Yes, basically setting him up for an embarrassment. Do you home work. If you don't know how, go back and read.