PLEASE HELP (:

Joanne has 20 books on crafts and cooking. she has 6 more cookbooks than craft books. how many of each does she have?

marin [14]

Answer:

Crafts books: 7

Cookbooks: 13

Step-by-step explanation:

Let x be the crafts book

Let y be the cookbooks

Solve for x:

Plug x and y in: x + y = 20
Re-write: y = x + 6
Plug in x + 6 instead of y: x + x + 6 = 20
Combine like terms: 2x + 6 = 20
Subtract 6 from each side, so it now looks like this: 2x = 14
Divide each side by 2 to cancel out the 2 next to x. It should now look like this: x = 7

Solve for y:

Re-use an equation from above: y = x + 6
Plug in the value of x: y = 7 + 6
7 + 6 = 13
So, y = 13

I hope this helps!

5 0

4 years ago

If a pair of regular dice are tossed once, use the expectation formula to determine the expected sum of the numbers on the upwar

Darya [45]

Answer:

The expected sum of the numbers on the upward faces of the two dice is 7.

Step-by-step explanation:

Consider the provided information.

If two pair of dice tossed the possible out comes are:

(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6)

(2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6)

(3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6)

(4, 1), (4, 2), (4, 3), (4, 4), (4, 5), (4, 6)

(5, 1), (5, 2), (5, 3), (5, 4), (5, 5), (5,6)

(6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6,6)

Now we need to find the expected sum of the numbers on the upward faces of the two dice.

The expected sums can be:

Sum: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12

Prob: 1/36, 2/36, 3/36, 4/36, 5/36, 6/36, 5/36, 4/36, 3/36, 2/36, 1/36

As we know that the expectation of experiment can be calculated as:

$P(S_1)\cdot S_1+P(S_2)\cdot S_2+........+P(S_n)\cdot S_n$

Here S represents the numerical outcomes and P(S) is the respective probability.

Substitute the respective values in the above formula.

$=2\times\frac{1}{36}+3\times\frac{2}{36}+4\times\frac{3}{36}+5\times\frac{4}{36}+6\times\frac{5}{36}+7\times\frac{6}{36}+8\times\frac{5}{36}+9\times\frac{4}{36}+10\times\frac{3}{36}+11\times\frac{2}{36}+12\times\frac{1}{36}\\=\frac{252}{36}\\=7$

Hence, the expected sum of the numbers on the upward faces of the two dice is 7.

8 0

4 years ago

Number 6 help. <br> .......................

hichkok12 [17]

Since it says only write a expression, you can do 45xM= ?/?

6 0

3 years ago

Have 22 more questions and need help will give brainliest to the correct answer and plz explain how u got that answer

dusya [7]

24. This answer would be A, or y=x^4. When the exponent is used, in each ordered pair, every time x is increased by 1, y is multiplied by 4, like in every exponent. 1 x 4 = 4. 4 x 4 = 16. 16 x 4 = 64. 64 x 4 = 256.

25. The answer is C, or C(n) = (0.90 + n) - 0.40. Your coupon subtracts 40 cents off of your total amount of cans of tuna, but the amount of tuna cans that you will buy is not stated, so that unknown number is n.

4 0

4 years ago

X/8-1/2=6 <br>what does that make?

slega [8]

Answer:

Step-by-step explanation:

$\frac x8-\frac12\ =\ 6\\\\{}\ \ \cdot8\qquad \cdot8\\\\x-4\ =\ 6\\\\{}\ +4\ \,\quad+4\\\\x\ =\ 10$

5 0

3 years ago