Question 1:
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Total points = 100
Total question = 40
Type of questions : 2-points question and 4-points questions
Assumed all 40 questions are 2-points questions.
Total points = 40 x 2 = 80
Difference in points = 100 - 80 = 20 points
Difference in the 2 type of questions = 4 - 2 = 2
Number of 4 marks questions = 20 ÷ 2 = 10
Number of 2 marks questions = 40 - 10 = 30
Answer: There are 10 4-marks questions and 30 2-marks questions.
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Question 2:
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Let x be the number of offices you need to clean.
Total cost = 315 + 4x
Total revenue = 25x
To break even,
315 + 4x = 25x
21x = 315
x = 15
Answer: You need to clean 15 offices to break even.
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Question 3:
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Total distance (including return trip) = 255 + 255 = 510 miles
Total time taken = 1.7 + 1.5 = 3.2 hours
Speed = Distance ÷ time
Speed = 510 ÷ 3.2 = 159.38 miles/hour
Answer: The average speed is 159.38 miles/hour
The rate of change is 25 because it goes 25 50 75 100 think of it like quarters
Mai's penny bank can hold 498 pennies without being full.
Answer:
5<b-3
Add 3 on both sides
8<b
The variable will always go on the left side of the equation. To flip the equation, you must also flip the less than sign to a greater than sign.
b>8
Hope I helped!
The probability that a two-digit number selected at random has a tens digit less than its units digit is 0.2667 (4/15).

There are 90 two-digit numbers (99-9). Of these, six numbers are divisible by 15 (15, 30, 45, 60, 75, 90). This is also divisible by 5. Therefore, the preferred case is 30-6 = 24. Therefore, the required probability is 24/90 = 4/15.
The probability of an event can be calculated by simply dividing the number of favorable results by the total number of possible results using a probabilistic expression. Whenever you are uncertain about the outcome of an event, you can talk about the probability of a particular outcome, that is, its potential.
Learn more about probability here: brainly.com/question/24756209
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