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3 years ago

A club has 12 members. In how many ways can we select four members to go on a trip?

1 answer:

3 0

This is the number of combinations of 4 from 12

12C4 = 12!
----------
4! 8!

= 12*11*10*9 11*5*9 = 495
-------------- =
4*3*2*1

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What is 1 1/4 × 4 3/4 =

Luden [163]

First, we need to turn this into an improper fraction. Therefore we have: 1 1/4 = 5/4 and 4 3/4 = 19/4
Now we multiply across and eliminate as needed.
5/4 * 19/4 = 95/16
Finally, we reduce and convert to a mixed fraction.
16 goes into 95, 5 times with a remainder of 15. Therefore, we can conclude that our answer is: 5 15/16.

4 0

3 years ago

4. A boat shop rents its boats for $20 per hour and charges a flat fee of

ruslelena [56]

Answer:

4 hours

Step-by-step explanation:

Let x = # of hours

22x + 10 = 98

-10 -10

____________

22x = 88

x = 4

8 0

3 years ago

The diameter, D, of a sphere is 15.2m. Calculate the sphere's volume, V.

Lena [83]

Using the formula:
V= 1/6 πd^3
V ≈ 1838.78

5 0

3 years ago

Could someone help me understand how to solve this?

monitta

Answer:

Amount in 4% account: $550

Step-by-step explanation:

Use simple interest formula $I=P\cdot r\cdot t,$ where

I = interest

P = principal

r = rate (as decimal)

t = time.

<u>4% account:</u>

$P_1=x\\ \\r_1=0.04\\ \\t_1=1,$

then

$I_1=x\cdot 0.04\cdot 1=0.04x$

<u>5% account:</u>

$P_2=1,500-x\\ \\r_2=0.05\\ \\t_2=1,$

then

$I_2=(1,500-x)\cdot 0.05\cdot 1=0.05(1,500-x)$

You have earned $69.50 in total, so

$I_1+I_2=69.50\\ \\0.04x+0.05(1,500-x)=69.50\\ \\4x+5(1,500-x)=6,950\\ \\4x+7,500-5x=6,950\\ \\4x-5x=6,950-7,500\\ \\-x=-550\\ \\x=550\\ \\1,500-x=1,500-550=950$

Amount in 4% account: $550

Amount in 5% account: $950

8 0

3 years ago

Find the lateral area for the pyramid with the equilateral base.

Dafna11 [192]

Answer:

Option A is the correct answer.

Explanation:

The given pyramid has 3 lateral triangular side as shown below.

Base of triangle = 12 unit

We need to find perpendicular.

By Pythagoras theorem we have

Perpendicular² = 10²-6²

Perpendicular = 8 unit

So area of 1 lateral triangle = 1/2 x Base x Perpendicular.

= 1/2 x 12 x 8 = 48 unit²

Area of lateral side = 3 x 48 = 144 unit²

Option A is the correct answer.

7 0

3 years ago

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