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3 years ago

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Students are given 3 minutes to complete each multiple-choice question on a test and 8 minutes for each free-response question.

There are 15 questions on the test and the students have been given 55 minutes to complete it. A Table titled Test Time, showing Number of Questions, Time per Item in minutes, and Total Time in minutes. The first row shows Multiple Choice, with m, 3, and 3 m. The second row shows Free Response, with 15 minus m, 8, and x. The third row shows Total, with 15, blank, and 55. Which value could replace x in the table? 7 – m 23 – m 8(15 – m) 8(15) – m

1 answer:

weqwewe [10]3 years ago

6 0

Answer:

8(15-m)

Step-by-step explanation:

By looking at the options, we can understand that the right one is 8(15-m), since we need to multiply the time by the number of question.

Also, we can check that result by arranging an equations usint the total time.

55 = 3m - 8(15-m)

55 = 3m - 120 + 8m

55 = 11m - 120

55 + 120 = 11m

175 = 11m

m = 175/11 = 15.91

55 = 3*15.91 - 8(15-15.91) = 47.73 - 120 + 127.28 = 55.01 ≈ 55

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Igoryamba

Answer:

Step-by-step explanation:

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Use the opposite angles in an inscribed quadrialteral theorem,

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Substitute,

14x - 7 + 8z = 180

Simplify,

22z - 7 = 180

Inverse operations,

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2 years ago

Read 2 more answers

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JulijaS [17]

Answer:

The amount of oil was decreasing at 69300 barrels, yearly

Step-by-step explanation:

Given

$Initial =1\ million$

$6\ years\ later = 500,000$

Required

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To do this, we make use of the following notations

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So:

$\frac{dA}{dt} = kA$

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$\frac{dA}{dt} = kA$

Multiply both sides by dt/A

$\frac{dA}{dt} * \frac{dt}{A} = kA * \frac{dt}{A}$

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Integrate both sides

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So, we have:

$A = Ce^{kt}$

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$1000000 = C*1$

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Answer:

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