Answer:
John is 19 and his sister is 23.
Step-by-step explanation:
See attached image.
Using it's concept, it is found that a good estimate for the probability of drawing out a green block from the bag is of 0.67 = 67%.
<h3>What is a probability?</h3>
A probability is given by the <u>number of desired outcomes divided by the number of total outcomes</u>.
In this problem, to get a good estimate, we get the probability taking the outcomes from the sample, that is, 67 green blocks out of 100 blocks, hence:
p = 67/100 = 0.67.
A good estimate for the probability of drawing out a green block from the bag is of 0.67 = 67%.
More can be learned about probabilities at brainly.com/question/14398287
The scuba diver's position relative to sea level after the 4.6 minutes is 5.1 ft.
Given:
A scuba diver descends in the water at a rate of 23 1/2 feet per minute for 2.6 minutes.
A scuba diver ascends at a rate of 28 feet per minute for 2 minutes after seeing a big fish.
To find :
The scuba diver's position relative to sea level after the 4.6 minutes.
Solution:
Rate of a scuba diver descending in the water for 2.6 minutes = 

Distance covered by a scuba diver in 2.6 minutes = 

Rate of a scuba diver ascending for 2 minutes = 

Distance covered by a scuba diver in 2 minutes = 

The position of scuba diver after 4.6 minutes relative to sea level:

The scuba diver's position relative to sea level after the 4.6 minutes is 5.1ft.
Learn more about ascending rate and descending rate here:
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