(28 * x) -42 = 154
28x - 42 = 154
28x = 196
the unknown number is 7
Providing a short wikipedia definition here: "In mathematics, a rational number is any number that can be expressed as the quotient or fraction"
So any fraction would work for this question I believe?
Irrational because it’s not a perfect square.
Answer:
He performed better in the 800 m race
Step-by-step explanation:
Obtain the standardized score for each event :
Zscore = (score - mean) / standard deviation
1000 meter :
Mean = 4.5 ; Standard deviation = 0.75 ; x = 4.1
Zscore = (4.1 - 4.5) / 0.75
Zscore = - 0.4 / 0.75 = - 0.5333
800 meter :
Mean = 3.2 ; Standard deviation = 0.4 ; x = 3
Zscore = (3 - 3.2) / 0.4
Zscore = - 0.2 / 0.4 = - 0.5
-0.5 > - 0.533
Hence, he performed better in the 800 m race