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4 years ago

Joanna has a total of 7 rolls of coins worth $23. She has rolls of dimes worth $5 each, and

Mathematics

1 answer:

yawa3891 [41]4 years ago

6 0

Answer:

3 rolls of dimes and 4 rolls of nickels

Step-by-step explanation:

Number of rolls of dimes = x

Number of rolls of nickels = y

Total number of rolls = 7

x + y = 7 -------------------(i)

Total amount = $ 23

5x + 2y = 23 ----------------(ii)

Multiply equation (i) by -2. So when we are adding, y will be eliminated and you will get the number of rolls of dimes.

(i)*(-2) -2x - 2y = -14

(ii) <u>5x + 2y = 23</u> {Now add}

3x = 9

x = 9/3

x = 3

Plug in the value of x in equation (i)

3 +y = 7

y = 7- 3

y = 4

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If you help ill give you some of my banana milk...

snow_tiger [21]

Given:

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The domain of the given function.

Solution:

Domain is the set of input values.

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3 years ago

Hi quick whats 18 x 1.25 <br> step by step !!

Ivan

Answer:

22.5

Step-by-step explanation:

125

x 18

---------

1. first set up your problem

2 4

125

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1000

2. next multiply the 8 by 5 getting 40, drop the 0 anf move the 4 to the top above 2.

3. multiply 8 by 2 getting 16, then add the 4 you have ontop of the 2 to the 16 getting 20. Drop the 0 and bring the 2 over and place it above the one.

4. multiply 8 by 1 getting 8 then add the 2 above the 1 to 8 getting 10. Then put the ten infront of the tw zeros. 1000

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Next add a 0 as a place filler under the 0 at the end.

125

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1250

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3 0

3 years ago

Simplify the following expression.

tankabanditka [31]

The answer is 2/3

or in decimal form: 0.6 repeated

7 0

3 years ago

A map is drawn using a scale of 1cm/80mi

Setler79 [48]

Answer:

B) 3.5cm

Step-by-step explanation:

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4 0

3 years ago

Eric was rock climbing. At one point, he stopped and climbed straight down 2\dfrac{1}{2}2

nikitadnepr [17]

The equation that matches the given situation is $-2\frac{1}{2}+6\frac{3}{4}=?$ . So, after two moves, Eric's elevation changed $4\frac{1}{4}$ meters above.

We know that in mathematics, subtraction means removing something from a group or a number of things. What is left in the group gets smaller when we subtract. The minuend is the first element we use. The subtrahend is the part that is being removed. The difference is the portion that remains after subtraction.

Assume that "negative" means climbing down and "positive" means climbing up. We must locate the elevation change in this area.

Given that Eric climbed straight down $2\frac{1}{2}$ meters. So we can write $-2\frac{1}{2}$ .

Again Eric climbed straight up $6\frac{3}{4}$ meters. So, we can write $6\frac{3}{4}$ .

Then the change = $-2\frac{1}{2}+6\frac{3}{4}$

= $-\frac{(2*2+1)}{2}+\frac{6*4+3}{4}$

= $-\frac{5}{2} +\frac{27}{4}$

= $\frac{-(5*2)+27}{4}$

= $\frac{-10+27}{4}$

= $\frac{17}{4}$

= $\frac{4*4+1}{4}$

= $4\frac{1}{4}$

Therefore, the equation that matches the given situation is $-2\frac{1}{2}+6\frac{3}{4}=?$ . So, after two moves, Eric's elevation changed $4\frac{1}{4}$ meters above.

Learn more about subtraction here -

brainly.com/question/24116578

#SPJ10

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2 years ago