Question

Please answer little urgent

Answer 1

Answer:

The resistance of the group of 3 resistors is equal to

R = 30 V / 7.5 A = 

4 ohm.

Let R3 be the resistance of the third resistor, then

1/R = 

1/10 + 1/12 + 1/R3

so,

1/4 = 1/10 + 1/12 + 1/R3

1/R3 = 1/4 

- 1/10 - 1/12 

= 15/60 - 6/60 - 5/60 

= 4/60

hence 

R3 = 60/4 = 15 ohm