An inverted pyramid is being filled with water at a constant rate of 30 cubic centimeters per second. the pyramid, at the top, has the shape of a square with sides of length 4 cm, and the height is 8 cm. find the rate at which the water level is rising when the water level is 5 cm.

The rate at which the water level is rising when the water level is 5 cm is;

dh/dt = 1.6 cm/s

We are told that;

length of square side; s = 4 cm

height of pyramid; h = 8 cm

volumetric rate; dV/dt = 30 cm³/s

Since the base is square shaped and we know that area of a square = s², then we can say that;

Volume of pyramid = ¹/₃s²h

The pyramid has a height of 8 cm and length of its' square base side is 8 cm.

Now, regardless of the water height, the surface of the water will always be square shaped. This implies that the ratio of the height to the top side of square will always be the same. Thus, we can say that; s = 4/8 h = h/2

Thus, Volume is;

V = ¹/₃ × (h/2)² × h

V = ¹/₃ × h³/4

V = h³/12

dV/dt = (3h²/4) dh/dt

Plugging in the relevant values gives;

30  = (3 × 5²/4) dh/dt

120 = 75 dh/dt

dh/dt = 120/75

dh/dt = 1.6 cm/s

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4.8cm/s

Step-by-step explanation:

We are given that an inverted pyramid.

Base of pyramid=4cm

Height of pyramid=8 cm

We have to find the rate at which the water level is rising when the water level is 5 cm.

Volume of pyramid=

As the height changes from 8 to h.

Therefore, the volume of pyramid for given height is given by

Differentiate w.r.t time

Substitute h=5

Hence, the rate at which the water level is rising when the water level is 5cm=4.8 cm/s

the results from a pre-test for students for the year 2000 and the year 2010 are illustrated in the box plot. what do these results tell us about how students performed on the 29 question pre-test for the two years?

if we compare only the lowest and highest scores between the two years, we might conclude that the students in 2010 did better than the students in 2010. this conclusion seems to follow since the lowest score of 8 in 2010 is greater in value than the lowest score of 6 in 2000. also, the highest score of 28 in 2010 is greater in value than the highest score of 27 in 2000.

but the box portion of the illustration gives us more detailed information. the middle bar in each box shows us that the median score of 20 in 2000 is greater in value than the median score of 17 in 2010. further, we note that the box and whiskers divide the illustration into four pieces. each of these four pieces represents the same portion of students. so, the upper half of the students in 2000 scored in the same score range as the upper one-fourth of the students in 2010, see the illustration at a score of 20.

by considering the upper one-fourth, upper half, and upper three-fourths instead of just the lowest and highest scores, we would conclude that the students as a whole did much better in 2000 than in 2010. we would conclude that as a whole the students in 2010 are less prepared than the students in 2000.

in this section, we discuss box-and-whisker plots and the five key values used in constructing a box-and-whisker plot. the key values are called a five-number summary, which consists of the minimum, first quartile, median, third quartile, and maximum.

step-by-step explanation: