A sludge pool is filled by two inlet pipes. One pipe can fill the pool in 14 days and the other pipe can fill it in 21 days. However, if no sewage is added, waste removal will empty the pool in 39 days. How long will it take the two inlet pipes to fill an empty pool?

if you explain the the question more correctly i might be able to answer this better

step-by-step explanation:

answer: 33 ( approx)

step-by-step explanation:

since, in the linear regression formula, the slope is the a in the equation y = b + ax ( by comparing it with the general equation of line y = mx + c )

where,

here given table is,

price ($), x   :           18         23       25       29       30       33

pairs sold, y :         16         13         10       8         6       2

so, ,   ,   ,

and   ,

thus, slop of the given line is,

⇒  

⇒   ≈ 33

and?

step-by-step explanation: