(i) Calculate the mean and standard deviation for these weekly incomes.

Mathematics

1 answer:

polet [3.4K]3 years ago

7 0

Answer:

Mean = 272.3

sd = 37.7

Step-by-step explanation:

Mean = sum/n

(221+248+251+255+259+263+264+272+291+297+374) ÷ 11

= 2995/11

= 272.2727273

Variance = (sum of x²)/n - mean²

[(221²+248²+251²+255²+259²+263²+264²+272²+291²+297²+374²)/11] - (2740/11)²

= (831067/11) - (2995/11)²

= 1419.107438

sd² = variance

sd = sqrt(1419.107438)

sd = 37.67104243

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USPshnik [31]

Answer:

The ordered pair generated from the equation is (1, 6).

Step-by-step explanation:

An ordered pair is a pair of numbers, representing two variables, in a specific order. For instance, (x, y) = (1, 2) here x = 1 and y = 2.

The equation provided is:

$y=2x+4$

Check for all the options:

A (1, 6): $y=2x+4\Rightarrow\ 6=(2\times 1) +4\Rightarrow\ 6=6$
B (1, 2): $y=2x+4\Rightarrow\ 2=(2\times 1) +4\Rightarrow\ 2\neq 6$
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Thus, the ordered pair generated from the equation is (1, 6).

8 0

3 years ago

A tank has capacity 6 L and initially contains 11 mg of salt dissolved in 3 L of water. A solution containing 1 mg/L of salt ent

BlackZzzverrR [31]

Answer:

The answer is below

Step-by-step explanation:

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