Three resistors of 2, 3 and 5 ohms are connected in series. The total resistance is

Explanation

Series resistances simply add, giving 10 ohms, and the same current passes through each while the voltages divide in proportion to the resistances. In parallel the reciprocals add, which for these values gives about 0.97 ohms, always less than the smallest resistor. Recognising which arrangement the question describes is half the work.