What's is 2/5 of 20 A. 4 B. 8 C. 20 2/5 D. 40

Hi :), im really struggling with this. Just wanted to know if anyone can explain step by step for me please. Id really appreciat

Dvinal [7]

Answer:

314 m²

Step-by-step explanation:

the formula for the surface area of a sphere (As) is

As = 4×pi×r²

the radius r (half of the diameter) is clearly indicated as 5m.

so, As = 4×3.14×5² = 4×3.14×25

I don't even need a calculator for this, as 4×25 = 100

so, As = 100×3.14 = 314

(you know, when multiplying by 10, the decimal point moves right one position. multiply by 100 it moves 2 positions, and so on).

7 0

3 years ago

Kareem made $273 for 13 hours of work. at the same rate, how many hours would he have to make to work to make $147?

klio [65]

Answer:

105

Step-by-step explanation:

273/13 × 5= 105

That's the correct answer

5 0

2 years ago

Please help me! I have problem understanding. Please give me workings

Ivanshal [37]

Answer:

A)7

B)14

C)20

D)18

Step-by-step explanation:

For example 2/5 of 80

2/5 x 80/1 =32 Cross cancel

7 0

4 years ago

Two teachers purchase supplies for their classrooms.

inna [77]

Answer:

Cost of One Journal = $3.99

Cost of One pen = $0.59

Step-by-step explanation:

Let

Cost of One Journal = x

Cost of One pen = y

We can make equation from given statements.

Mr. Bowden purchases 18 journals and 40 pencils for $95.42.

$18x+40y=95.42$

Ms. Jacinto purchases 11 journals and 16 pencils for $53.33.

$11x+16y=53.33$

Now solving these equations to find the value of x

$18x+40y=95.42--eq(1)\\11x+16y=53.33--eq(2)$

Multiply eq(1) with 2 and eq(2) with 5

$36x+80y=190.84\\55x+80y=266.65\\-\:\:\:\:-\:\:\:\;\:\:\:\:\:\:\:-\\---------\\-19x=-75.81\\x=\frac{-75.81}{-19}\\x=3.99\\$

We get the value of x is: x=3.99

Now, putting value of x in equation 1 to find value of y.

$18x+40y=95.42\\18(3.99)+40y=95.42\\71.82+40y=95.42\\40y=95.42-71.82\\40y=23.6\\y=\frac{23.6}{40}\\y= 0.59$

So, we get the value of y: y = 0.59

Now, finding the costs:

Cost of One Journal = x = $3.99

Cost of One pen = y = $0.59

7 0

3 years ago

A regular hexagon is shown.

-BARSIC- [3]

Answer:

(C)9 in.

Step-by-step explanation:

The apothem of a regular polygon is a line segment from the center to the midpoint of one of its sides.

Given the hexagon with a radius of 10 inches

The apothem AB divides the side of the hexagon into two equal parts of 5 Inches as seen in the attached diagram.

Using Pythagoras Theorem

$10^2=5^2+|AB|^2\\|AB|^2=10^2-5^2\\|AB|^2=75\\|AB|=\sqrt{75}\\ |AB|=8.66$ in\\\approx$ 9 in (rounded to the nearest inch)$

The correct option is C

8 0

3 years ago

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