Two factory plants are making tv panels. yesterday, plant A produced twice as much as Plant B. 5% of the panels from Plant A and 4% of the panels from Plant B were defective. How many panels did Plant B produce, if the two plants together produced 980 defective panels?

7,000 panels

Step-by-step explanation:

Let the number of panel produced by plant B be x, this means plant A produced 2x. This is because what they produced is twice as much.

Now, we know 5% and 4% of the panels produced were defective and the total number of defectives is 980. This means that:

[5/100 * 2x] + [4/100 * x ] = 980

(0.05 * 2x) + (0.04x) = 980

0.1x + 0.04x = 980

0.14x = 980

x = 980/0.14 = 7,000 panels.