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3 years ago

A number is called evil if it has 666 in it. How many 7 digit numbers are evil?

Mathematics

1 answer:

defon3 years ago

5 0

Step-by-step explanation:

There are 5 different positions of 666:

666////

/666///

//666//

///666/

////666

The forward dashes represent any number from 0 to 9.

Case 1: "666////"

Number of ways = 10⁴ = 10,000.

Case 2: The other positions.

Since the 1st forward dash cannot be 0 (leading digit),

Number of ways for each position = 9 * 10³ = 9,000

Number of ways for all 4 positions = 9,000 * 4 = 36,000.

Total evil numbers = 10,000 + 36,000 = 46,000.

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Help please triangles and trig

Oksanka [162]

Answer:

$\sin L = \frac{3}{5}$

$\tan N = \frac{4}{3}$

$\cos L = \frac{4}{5}$

$\sin N = \frac{4}{5}$

Step-by-step explanation:

Given

The above triangle

First, we calculate the length LM using Pythagoras theorem.

$LN^2 = LM^2 + MN^2$

$10^2 = LM^2 + 6^2$

$100 = LM^2 + 36$

Collect like terms

$LM^2 = 100 - 36$

$LM^2 = 64$

Take positive square root

$LM=8$

Solving (a): Sin L

$\sin L = \frac{Opposite}{Hypotenuse}$

$\sin L = \frac{MN}{LN}$

$\sin L = \frac{6}{10}$

Simplify

$\sin L = \frac{3}{5}$

Solving (b): tan N

$\tan N = \frac{Opposite}{Adjacent}$

$\tan N = \frac{LM}{MN}$

$\tan N = \frac{8}{6}$

Simplify

$\tan N = \frac{4}{3}$

Solving (c): cos L

This calculated as:

$\cos L = \frac{Adjacent}{Hypotenuse}$

$\cos L = \frac{LM}{LN}$

$\cos L = \frac{8}{10}$

Simplify

$\cos L = \frac{4}{5}$

Solving (d): sin N

This is calculated using:

If $a + b = 90$

Then: $\sin a = \cos b$

So:

$\sin N = \cos L$

$\sin N = \frac{4}{5}$

8 0

3 years ago

At a school fundraiser, for every 12 boxes of chocalate sold a

meriva

Answer/Step-by-step explanation:

72/12=6

6x5=30

30 points.

5 0

2 years ago

The sum of two numbers is 72 the greater number is 8 more than the smaller number which equation can be used to solve for the sm

kobusy [5.1K]

Answer:

let x is the smaller number

bigger number is x + 8

The sum of two numbers is 72

x + (x+8) = 72

answer

x + (x + 8) = 72

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers

What number could be a common denominator for 1/5 and 5/6? 6 5 11 30

sukhopar [10]

30 because it is the first number that both 5 and 6 meet at

7 0

4 years ago

How much lace does she uses for he jewel box?

ozzi

4/5 * 5/6 = 4/6 = 2/3
She uses 2/3 yards of lace

8 0

3 years ago