Answer:
Step-by-step explanation:
2s + t = r
t = r - 2s
Let t represent Todd's age now.
.. 4(t -3) -(t -3) = 81 . . . . . . 3 years ago, their differnce in ages was 81.
.. 3t -9 = 81
.. t = (81 +9)/3 = 30
Todd is 30 now.
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You can also work this by considering "ratio units." 3 years ago, the ratio of their ages was 4:1, a difference of 3. That difference corresponds to 81 years, so each "ratio unit" represents 81/3 = 27 years. Todd's age then was 1 ratio unit, 27 years. Now, Todd's age is 30.
1. The number of sample size 1 jelly beans in a 2-liter jar is <u>645</u>.
2. The number of sample size 2 jelly beans in a 2-liter jar is <u>640</u>.
3. The number of sample size 3 jelly beans in a 2-liter jar is <u>637</u>.
<h3>What is a mathematical operation?</h3>
A mathematical operation is an expression involving the use of mathematical operands and operators to compute values.
Mathematical operations use variables, numbers, and operators (addition, subtraction, division, and multiplication).
<h3>Data and Calculations:</h3>
Total weight = 1,150g
Weight of the jar = 440g
The total weight of the jelly beans = 710g (1,150 - 440)
Sample Size 1: the number of jelly beans = 645 (710/22.0 x 20)
Sample Size 2: the number of jelly beans = 640 (710/22.2 x 20)
Sample Size 3: the number of jelly beans = 637 (710/22.3 x 20)
Thus, the number of jelly beans in a 2-liter jar depends on the sample size of the jelly beans.
Learn more about mathematical operations at brainly.com/question/20628271
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Blediana would have read a total of 12 Harry Potter books in 6 months.
If she read 10 books in 5 months, that would be 2 books per month. 6 months would allow her to lead a total of 12 books.