three resistors 2? 3?and 4?are connected in (a) series (b) parallel. find the equivalent resistance in each case.

Given -
R1- 2 ohm
R2 - 3 ohm
R3- 4 ohm

Equivalent resistance in series combination -
Rs = R1 + R2 + R3
Rs = (2+3+4) ohm
Rs = 9 ohm

Equivalent resistance in parallel combination -
1/Rp = 1/R1 + 1/R2 + 1/RE
1/ Rp = 1/2 + 1/3 + 1/4
1/Rp = 6+4+3/12
1/Rp = 13/12
Rp = 12/13 or 0.92