A 22-kilo ohm resistor having a tolerance of 10% has failed. You have on hand five resistors, valued at 120, 220, 47, 33 and 120-kilo ohm, respectively. What combination of these would you choose to re

I would choose to replace the failed resistor with a combination of 22-kilo ohm and 47-kilo ohm resistors in series. The 10% tolerance on the failed resistor gives us a range of 19.8 to 24.2 kilo ohms. Since we don't have any resistors that match this value exactly, we need to use a combination of resistors to get as close as possible. The 47-kilo ohm resistor has a tolerance of 5%, which gives us a range of 44.65 to 49.35 kilo ohms. Adding this in series with a 22-kilo ohm resistor gives us a total resistance range of 66.65 to 71.35 kilo ohms, which is within our required range of 19.8 to 24.2 kilo ohms. The other resistors on hand either have too high or too low of a value to be used in combination with the 22-kilo ohm resistor to achieve the required value range.