The main span of Bridge A ​(2300 ​feet) is​ _____ percent shorter than the main span of Bridge B ​(4700 ​feet).

7. Step-by-step explanation: By working backward, we determine Bob's initial product. Since we subtracted 3 to arrive at 1, his earlier total was 4. Dividing by 5 resulted in 4, indicating his original value was 20. Adding 6 to that gives us 14. We know that the multiplication of two numbers totals 14, specifically between 2 and 7, making the odd number 7.

<span>y = 2x + 20. Choice A is correct. Reasoning: Vlad first spends 20 minutes on his history assignment and then completes x math problems. Each math problem requires 2 minutes, so the time for math is 2x. Adding the two parts gives total time y = 20 + 2x, with x ≥ 0 and y ≥ 20.</span>

Response: B. 0.45

Detailed explanation:

According to the table provided, the total number of students is 137

The total of sophomore students is 35 + 42 = 77

Let A represent the event for sophomore students.

Thus, the probability of the students being sophomores is calculated as:

Out of these, the sophomore students who went to the jazz concert number 35

Let B denote the event of attending the jazz concert.

The probability of attending the jazz concert while being sophomores is calculated as:

Therefore, the probability that a student attended the jazz concert given that they are a sophomore is given by:-

To find the number of tails, subtract 225 from 500, yielding 275. So, we establish a ratio of 225 to 500, which needs to be simplified. Dividing both by 25 gives us 9 and 20 respectively. Therefore, the simplified ratio is 9:20.