Will mark correct answer answer brainliest! together, tran and luis take 6 hours to deliver newspapers. if tran works alone, it takes him 9 hours. how long would it take luis, working alone, to deliver all the newspapers? options: 12 hours 15 hours 18 hours 16 hours

It will take luis 18 hours

Step-by-step explanation:

1/a + 1/b = 1 /t

where a is  the time for one individual working alone

b  is the time the second individual working alone

t is the time the two individuals working together

let a = time for tran to work

b = time for luis  to work

1/9 + 1/b =1/6

multiply by 36b to clear the fractions

36b *(1/9 + 1/b) =1/6 * 36b

4b + 36 = 6b

subtract 4b from each side

36 = 2b

divide by 2

18 = b

It will take luis 18 hours

one that is bigger than 3 1/2

correct answer is c. just did it

step-by-step explanation: