Ernie's income is 4/5 of what it used to be and Jack's income is now twice what Ernie used to make. How much do they earn combined if Ernie used to make $6000? Let's be accurate as possible.
If Ernie's income is 4 / 5 of what it used to be, she is earning 4 / 5 * $6000 = $4800 now. Jack's income is now twice what Ernie used to make a total of 2 * $6000 = $12000. Combined, Ernie and Jack are making $12000 + $4800 = $16800.
The answer: 16800.