What is the value of the expression 8^−2 ?

A tailor used 6 2/3 yards of fabric to make hats. The amount of fabric needed to make each hat is 5/6 yard. How many complete ha

vfiekz [6]

Answer: The tailor made 8 complete hats

Step-by-step explanation:

Amount of fabrics available to make hat = 6 2/3 yards

1 hat requires = 5/6 yards

Number of hat to obtain from the available fabric = Amount of fabrics available to make hat / requirement of 1 hat

=(6 2/3) / (5/6)

(20/3) / (5/6)

20/3 x 6/5 = cancelling out, we are left with

4x2= 8 hats

or

(20/3) / (5/6)

6.6666 /0.83333

= 8.00002= 8 hats

6 0

3 years ago

John has $200 in his savings account. He deposits $50 each week. What is the rate of change?

Hunter-Best [27]

Answer:

50

Step-by-step explanation:

5 0

2 years ago

Read 2 more answers

A ball of radius 15 has a round hole of radius 5 drilled through its center. Find the volume of the resulting solid. Hint: The u

OverLord2011 [107]

Answer:

The volume of the ball with the drilled hole is:

$\displaystyle\frac{8000\pi\sqrt{2}}{3}$

Step-by-step explanation:

See attached a sketch of the region that is revolved about the y-axis to produce the upper half of the ball. Notice the function y is the equation of a circle centered at the origin with radius 15:

$x^2+y^2=15^2\to y=\sqrt{225-x^2}$

Then we set the integral for the volume by using shell method:

$\displaystyle\int_5^{15}2\pi x\sqrt{225-x^2}dx$

That can be solved by substitution:

$u=225-x^2\to du=-2xdx$

The limits of integration also change:

For x=5: $u=225-5^2=200$

For x=15: $u=225-15^2=0$

So the integral becomes:

$\displaystyle -\int_{200}^{0}\pi \sqrt{u}du$

If we flip the limits we also get rid of the minus in front, and writing the root as an exponent we get:

$\displaystyle \int_{0}^{200}\pi u^{1/2}du$

Then applying the basic rule we get:

$\displaystyle\frac{2\pi}{3}u^{3/2}\Bigg|_0^{200}=\frac{2\pi(200\sqrt{200})}{3}=\frac{400\pi(10)\sqrt{2}}{3}=\frac{4000\pi\sqrt{2}}{3}$

Since that is just half of the solid, we multiply by 2 to get the complete volume:

$\displaystyle\frac{2\cdot4000\pi\sqrt{2}}{3}$

$=\displaystyle\frac{8000\pi\sqrt{2}}{3}$

5 0

3 years ago

What is the probability that the product of two dice is greater than<br> 15 on two separate rolls?

ratelena [41]

Answer:

25/324

Step-by-step explanation:

Make a table of possible products:

$\left[\begin{array}{ccccccc}&1&2&3&4&5&6\\1&1&2&3&4&5&6\\2&2&4&6&8&10&12\\3&3&6&9&12&15&18\\4&4&8&12&16&20&24\\5&5&10&15&20&25&30\\6&6&12&18&24&30&36\end{array}\right]$

Of the 36 results, 10 are greater than 15.

The probability the product is greater than 15 on a single roll is 10/36 = 5/18.

The probability the product is greater than 15 on two rolls is (5/18)² = 25/324.

4 0

3 years ago

(11/x^2-25)+(4/x+5)= 3/x-5

Ierofanga [76]

$\bf \textit{difference of squares}
\\ \quad \\
(a-b)(a+b) = a^2-b^2\qquad \qquad 
a^2-b^2 = (a-b)(a+b)\\\\
-------------------------------\\\\
\cfrac{11}{x^2-25}+\cfrac{4}{x+5}=\cfrac{3}{x-5}\implies \cfrac{11}{x^2-5^2}+\cfrac{4}{x+5}=\cfrac{3}{x-5}$

$\bf \cfrac{11}{(x-5)(x+5)}+\cfrac{4}{x+5}=\cfrac{3}{x-5}\impliedby 
\begin{array}{llll}
\textit{notice, LCD is }(x-5)(x+5)\\
\textit{so let's multiply all by it}\\
\textit{to toss the denominators}
\end{array}$

$\bf (x-5)(x+5)\left( \cfrac{11}{(x-5)(x+5)}+\cfrac{4}{x+5} \right)=(x-5)(x+5)\left( \cfrac{3}{x-5} \right)
\\\\\\
11+4(x-5)=3(x+5)\implies 11+4x-20=3x+15
\\\\\\
4x-9=3x+15\implies x=24$

8 0

3 years ago