Study Guide 8, Self Test 5, Q 1

The 10 V is applied across each of the resistors.
For R₁: I₁ = V / R₁ = 10 / 250 = 0.04 A

For R₂: I₂ = V / R₂ = 10 / 3330 = 0.0030 A

There are 2 ways to determine the third and last current:

1. As before For R₃: I₃ = V / R₃ = 10 / 147 = 0.068 A
Notice, as required: 0.04 + 0.0030 + 0.068 = 0.111 A

2. Knowing that the total current must be 0.111 A then
I₃ = 0.111 - I₁ - I₂ = 0.111 - 0.04 - 0.0030 = 0.068 A as in 1.