Question

If two readings arc 8.0 and 8.4, what possible values for the third reading will make the average pH normal? Are these third readings likely? Explain.

Answer 1

Answer:

Let x be the third reading of the pH level.

The acidity of pool is normal when the average pH reading measurement is between 7.2 and 7.8

The first two measurement are 7.48 and 7.85

The average

⇒ 37.48+7.85+x <7.8

⇒7.48+7.85+x<23.4

⇒15.33+x<23.4

⇒x<23.4−15.33

⇒x<8.07

Similarly , the average

⇒ 37.48+7.85+x>7.2

⇒7.48+7.85+x>21.6

⇒15.33+x>21.6

⇒x>21.6−15.33

⇒x>6.27

Thus the range third reading of the acidity of the pool should be 6.27<x<8.07