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3 years ago

Matt is three times as old is Jessica. The sum of their ages will total 56. How old are they now?

Mathematics

1 answer:

N76 [4]3 years ago

4 0

Answer:

step 1: 3x+x=56

step 2: 4x=56

step 3: x=14

Jessica is 14. Matt is 3 times her age so Matt is 42. 14+42 equals 56.

Step-by-step explanation:

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This year, a small business had a total revenue of 20,100. If this is 34% more than their total revenue the previous year, what

andre [41]

There total revenue was like 7k or something

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2 years ago

The volume of a right circular cone with radius r and height h is V = pir^2h/3.

Scorpion4ik [409]

The question is incomplete. The complete question is :

The volume of a right circular cone with radius r and height h is V = pir^2h/3. a. Approximate the change in the volume of the cone when the radius changes from r = 5.9 to r = 6.8 and the height changes from h = 4.00 to h = 3.96.

b. Approximate the change in the volume of the cone when the radius changes from r = 6.47 to r = 6.45 and the height changes from h = 10.0 to h = 9.92.

a. The approximate change in volume is dV = _______. (Type an integer or decimal rounded to two decimal places as needed.)

b. The approximate change in volume is dV = ___________ (Type an integer or decimal rounded to two decimal places as needed.)

Solution :

Given :

The volume of the right circular cone with a radius r and height h is

$V=\frac{1}{3} \pi r^2 h$

$dV = d\left(\frac{1}{3} \pi r^2 h\right)$

$dV = \frac{1}{3} \pi h \times d(r^2)+\frac{1}{3} \pi r^2 dh$

$dV = \frac{2}{3} \pi r h (dr)+\frac{1}{3} \pi r^2 dh$

a). The radius is changed from r = 5.9 to r = 6.8 and the height is changed from h = 4 to h = 3.96

So, r = 5.9 and dr = 6.8 - 5.9 = 0.9

h = 4 and dh = 3.96 - 4 = -0.04

Now, $dV = \frac{2}{3} \pi r h (dr)+\frac{1}{3} \pi r^2 dh$

$dV = \frac{2}{3} \pi (5.9)(4)(0.9)+\frac{1}{3} \pi (5.9)^2 (-0.04)$

$dV=44.484951 - 1.458117$

$dV=43.03$

Therefore, the approximate change in volume is dV = 43.03 cubic units.

b). The radius is changed from r = 6.47 to r = 6.45 and the height is changed from h = 10 to h = 9.92

So, r = 6.47 and dr = 6.45 - 6.47 = -0.02

h = 10 and dh = 9.92 - 10 = -0.08

Now, $dV = \frac{2}{3} \pi r h (dr)+\frac{1}{3} \pi r^2 dh$

$dV = \frac{2}{3} \pi (6.47)(10)(-0.02)+\frac{1}{3} \pi (6.47)^2 (-0.08)$

$dV=-2.710147-3.506930$

$dV= -6.22$

Hence, the approximate change in volume is dV = -6.22 cubic units

8 0

2 years ago

Will give brainliest answer to whoever gets this correct.

yanalaym [24]

draw an imaginary line down from the 1 dimension so you have a rectangle that is 1 by 24

area = L x w = 24 * 1 = 24 square units

now you have a triangle that is 7 at the bottom and 24 tall

area of triangle = 1/2 x base x height

so you have 1/2 * 7 * 24 which =84 square units

total area = 84 + 24 = 108 units^2

please mark brainliest

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3 years ago

Help me find the rate of change for these points listed here, and also write an equation:

valentinak56 [21]

54-2/0-3=-17,3=a
Y=-17,3x+54 b=54 because its the initial value of y when x =0
When x=1 y=36,7
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2 years ago

sally has 20 coins in her piggy bannk, all dimes and quarters. the total amount of money is $3.05. how many of each coin does sh

VMariaS [17]

D=dimes
q=quarters

d + q = 20
.10d + .25q = 3.05

d=-q + 20

.10(-q + 20) +.25q = 3.05
-.10q + 2 + .25 = 3.05
.15q + 2 = 3.05
.15q + 2 - 2 = 3.05 - 2
.15q = 1.05
.15q/.15 = 1.05/.15
q = 7

d + 7 = 20
d + 7 - 7 = 20 - 7
d = 13

Sally has 7 quarters and 13 dimes.
Hope this helps!

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3 years ago