1. The ratio of boys to girls in Mr. Okafor's after-school club is the same as the ratio of boys to girls in Ms. Williams' after
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Answer: Hope it helps...
Step-by-step explanation: mark as an brainliest... if so
Answer:
An we can use the normal standard table and the following difference and we got this result:
Step-by-step explanation:
Assuming this statement to complete the problem "with a standard deviation 5 mpg"
We have the following info given:
represent the mean
represent the deviation
We have a sample size of n = 54 and we want to find this probability:
And for this case since the sample size is large enough >30 we can apply the central limit theorem and then we can use this distribution:
And we can use the z score formula given by:
And replacing we got:
An we can use the normal standard table and the following difference and we got this result:
Step-by-step explanation:
The upstream speed is S / t₁, and the downstream speed is S / t₂.
If we say f is the speed of the fish in calm water, and r is the speed of the river, then:
f − r = S / t₁
f + r = S / t₂
If we say T is the time it takes to cross the river, then the speed perpendicular to the river is ℓ/T, the speed parallel to the river is r, and the overall speed is f.
Using Pythagorean theorem:
f² = (ℓ/T)² + r²
f² − r² = (ℓ/T)²
(f − r) (f + r) = (ℓ/T)²
(S / t₁) (S / t₂) = (ℓ/T)²
S² / (t₁ t₂) = (ℓ/T)²
(t₁ t₂) / S² = (T/ℓ)²
√(t₁ t₂) / S = T/ℓ
T = ℓ√(t₁ t₂) / S
