<span>The amount of dissolved oxygen in the Missouri River would decrease if large amounts of chemical waste were dumped into it. It would decrease because the chemical waste would feed on the microorganisms and reduce the amount of oxygen in the river.</span>
divide the two:
52.50 / 7 = 7.50 per hour
Answer:
9a - 2b
Step-by-step explanation:
6a - 6b +3a +4b . . . . . . . we assume your _ is supposed to be -
= a(6 +3) +b(-6 +4)
= 9a -2b
Answer:
Mean age: 48
Standard deviation: 4
Step-by-step explanation:
a) Mean
The formula for Mean = Sum of terms/ Number of terms
Number of terms
= 42 + 54 + 50 + 54 + 50 + 42 + 46 + 46 + 48+ 48/ 10
= 480/10
= 48
The mean age is 48
b) Standard deviation
The formula for Standard deviation =
√(x - Mean)²/n
Where n = number of terms
Standard deviation =
√[(42 - 48)² + (54 - 48)² + (50 - 48)² +(54 - 48)² + (50 - 48)² +(42 - 48)² + (46 - 48)² + (46 - 48)² + (48 - 48)² + (48 - 48)² / 10]
= √-6² + 6² + 2² + 6² + 2² + -6² + -2² + -2² + 0² + 0²/10
=√36 + 36 + 4 + 36 + 4 + 36 + 4 + 4 + 0 + 0/ 10
=√160/10
= √16
= 4
The standard deviation of the ages is 4