The resistances of commercially-available discrete resistors are restricted to particular sets. For example, the available values of resistors with 10% tolerance are selections from the E12 set multiplied by a power of ten from 100 through 105. The E12 set is:
E12={10,12,15,18,22,27,33,39,47,56,68,82}
Thus, you can buy 10% resistors with a nominal resistance of 330Ω or 33kΩ, but not 350Ω. Furthermore, the "tolerance" means that if you buy a 10% 390Ω resistor you can be sure that its resistance is between 351Ω and 429Ω.

In this problem we need to choose 10% resistors to make a current divi

Question

The resistances of commercially-available discrete resistors are restricted to particular sets. For example, the available values of resistors with 10% tolerance are selections from the E12 set multiplied by a power of ten from 100 through 105. The E12 set is:
E12={10,12,15,18,22,27,33,39,47,56,68,82}
Thus, you can buy 10% resistors with a nominal resistance of 330Ω or 33kΩ, but not 350Ω. Furthermore, the "tolerance" means that if you buy a 10% 390Ω resistor you can be sure that its resistance is between 351Ω and 429Ω.

In this problem we need to choose 10% resistors to make a current divi

anonymous · Answer

i am still not getting it...i am confused

kenljw · Answer

general resistors a R(1+-x)
x is the tolerance
The ones mentioned come with x = .05, .1, .2
There are others available with x = .01, generally metal film, some come standard and some not
There's all available x = .001 but have less standard range
Aside from resistor tolerance there is also associated temperature coefficient.
To find these and other available there's a number a electronic catalogs either through mail or online, one source is Digt-Key