Roberto overtakes Juanita at the rate of (7.7 mi)/(11 h) = 0.7 mi/h. This is the difference in their speeds. The sum of their speeds is (7.7 mi)/1 h) = 7.7 mi/h.
Roberto walks at the rate (7.7 + 0.7)/2 = 4.2 mi/h.
Juanita walks at the rate 4.2 - 0.7 = 3.5 mi/h.
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In a "sum and diference" problem, one solution is half the total of the sum and difference. If we let R and J be the respective speeds of Roberto and Juanita, we have
R + J = total speed
R - J = difference speed
Adding these two equations, we have
2R = (total speed + difference speed)
R = (total speed + difference speed)2 . . . . . as computed above
Answer:
x = ±2sqrt(2)
Step-by-step explanation:
x^2 = 8
Take the square root of each side
sqrt(x^2) = ±sqrt(8)
x = ±sqrt(4*2)
We know that sqrt(ab) = sqrt(a)sqrt(b)
x = ±sqrt(4)sqrt(2)
x = ±2sqrt(2)
(0.4+0.75)/0.5
Your answer is 2.3
UPDATE
the answer is either 2 (3/10) as a mixed number or 23/10 as an improper fraction
Answer:
Step-by-step explanation:
Given that Home sales has 95% confidence interval to estimate the average loss in home value.
a) If std deviation of losses doubles as 3000 from 1500, we have margin of error also increases. Because margin of error
= ±Critical value * Std error
= ±Critical value * Std dev/sqrt n
Hence we find that whenever std deviation increases the margin of error increases, for the same level of confidence.
b) Whenever confidence level increases, critical value increases and as a result margin of error increases. Hence by reducing from 95% to 90% confidence interval would be reduced. True
c) Instead of changing conf level, increasing sample size would give more reliale and accurate results.
