All categories

4 years ago

Question 13 of 20 :

Mathematics

1 answer:

grin007 [14]4 years ago

8 0

Answer:

C. 70.4

Step-by-step explanation:

22% × 320 =

(22 ÷ 100) × 320 =

(22 × 320) ÷ 100 =

7,040 ÷ 100 =

70.4

You might be interested in

Select all that are true!!!!!!

nignag [31]

Answer:

The first and 3rd answer

Step-by-step explanation:

7 0

4 years ago

When 7 is subtracted from two third of the square of a number it becomes 17 find the number

Dmitry [639]

Answer: 6 or -6

hello,

Step-by-step explanation:

Let say n the number

$\dfrac{2}{3} *n^2-7=17\\\Longrightarrow\ \dfrac{2}{3} *n^2=24\\\Longrightarrow\ n^2=\dfrac{3*24}{2}\\\Longrightarrow\ n^2=36\\\Longrightarrow\ (n-6)(n+6)=0\\\\n=6\ or\ n=-6\\$

8 0

3 years ago

Evaluate<br><br> 4 / 5/6<br> Give your answer as a mixed number in its simplest form.

saul85 [17]

If we evaluation the expression 4 ÷ 5/6, the result is $4\frac{4}{5}$ .

<h3>How to evaluate an expression?</h3>

Given that;

4 ÷ 5/6
Evaluation = ?

4 ÷ 5/6

4/1 ÷ 5/6

First, we flip the numerator and denominator of the second fraction and changing the operation to multiplication

4/1 × 6/5

( 4 × 6 ) / ( 1 × 5 )

24 / 5

$4\frac{4}{5}$

Therefore, if we evaluation the expression 4 ÷ 5/6, the result is $4\frac{4}{5}$ .

Learn more about Algebra Problems here: brainly.com/question/723406

#SPJ1

7 0

2 years ago

Solve 5x^2 − 3x + 17 = 9.

Vedmedyk [2.9K]

Answer:

The roots of the equation are x = $\frac{3+\sqrt{151}i}{10}$ and x = $\frac{3-\sqrt{151}i}{10}$

and there are no real roots of the equation given above

Step-by-step explanation:

To solve:

5x² − 3x + 17 = 9

⇒ 5x² − 3x + 17 - 9 = 0

⇒ 5x² − 3x + 8 = 0

Now,

the roots of the equation in the form ax² + bx + c = 0 is given as:

x = $\frac{-b\pm\sqrt{b^2-4ac}}{2a}$

in the above given equation

a = 5

b = -3

c = 8

therefore,

x = $\frac{-(-3)\pm\sqrt{(-3)^2-4\times5\times8}}{2\times5}$

x = $\frac{3\pm\sqrt{9-160}}{10}$

x = $\frac{3+\sqrt{-151}}{10}$ and x = $\frac{3-\sqrt{-151}}{10}$

x = $\frac{3+\sqrt{151}i}{10}$ and x = $\frac{3-\sqrt{151}i}{10}$

here i = √(-1)

Hence,

The roots of the equation are x = $\frac{3+\sqrt{151}i}{10}$ and x = $\frac{3-\sqrt{151}i}{10}$

and there are no real roots of the equation given above

7 0

3 years ago

when each edge of a cube is decreased by 1 cm, its volume is decreased by 91 cm^3 .Find the length of the a side of the original

Leokris [45]

Step-by-step explanation:

the original side length is x.

the volume of a block is length × width × height.

so, for a cube with all sides being equal, the volume in our case is x³ (x × x × x).

now, with the same formula but with every side shortened by 1 cm we get

(x-1)(x-1)(x-1) = x³ - 91 (the original volume minus 91)

now, we have to do the multiplications.

(x-1)(x-1) = x² - 2x + 1

(x²-2x+1)(x-1) = x³ - x² - 2x² + 2x + x - 1 = x³ -3x² + 3x -1

x³ - 3x² + 3x - 1 = x³ - 91

-3x² + 3x = -90

-x² + x = -30

x² - x = 30

x² - x - 30 = 0

the general solution to such a squared equation is

x = (-b ± sqrt(b² - 4ac))/(2a)

in our case

a = 1

b = -1

c = -30

x = (1 ± sqrt((-1)² - 4×1×-30))/(2×1) =

= (1 ± sqrt(1 + 120))/2 = (1 ± sqrt(121))/2 =

= (1 ± 11)/2

x1 = (1 + 11)/2 = 12/2 = 6

x2 = (1 - 11)/2 = -10/2 = -5

a negative number does not make any sense for a side length, so our solution is x = 6 cm.

the original side length of the cube is 6 cm.

to check :

6³ = 216

(6-1)³ = 5³ = 125

216 - 125 = 91

perfect.

8 0

2 years ago