Step-by-step answer:
Answer to problems of this kind is the reciprocal of the harmonic mean of the time required.
We need to find the average of the speeds, not the average of the time.
The respective speeds are 1/3 and 1/4.
The average of the speeds is therefore (1/3+1/4)/2 = 7/24 (harmonic mean of the time taken).
The time required is therefore the reciprocal of the unit speed,
T = 1/(7/24) = 24/7 = 3 3/7 minutes, or approximately 3.43 minutes.
To find the unit rate, you have to find how much each pound costs
so 14.25/3 is the expression that will get you the answer
14.25/3= 4.75
4.75 per pound is your answer
hope this helps
K+3 3/4=5 2/3-1 1/3
k+3 3/4=4 1/3
lets find the lcm first then multiply both sides by it but first change it to improper fraction
LCM is 12
[k+15/4]=[13/3]12
12k+45=52
12k=7
k=7/12
The probability of no boys being chosen will be 0.29.
<h3>What is probability?</h3>
Its basic premise is that something will almost certainly happen. The percentage of favorable events to the total number of occurrences.
Mr. Larsen's third-grade class has 22 students, 12 girls, and 10 boys.
Two students must be selected at random to be in the fall play.
Then the probability of no boys being chosen will be
Total event = ²²C₂ = 231
Favorable event = ¹²C₂ = 66
Then the probability will be
P = 66 / 231
P = 0.2857
P ≅ 0.29
More about the probability link is given below.
brainly.com/question/795909
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