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3 years ago

A pile of 55 coins, consisting of nickels and dimes, is worth $3.90. find the number of each.

2 answers:

8 0

<span>N + D = 55 coins (1) (N stands for nickels, 5N + 10D = 390 cents (2) D stands for dimes) Simplify (2) by canceling the factor 5 in both sides: N + 2D = 78 (3) Subtract eq(1) from eq(3). You will get D = 78 - 55 = 23. Answer. 23 dimes and 55-23 = 32 nickels. Check. 23*10 + 32*5 = 390 cents</span>

kari74 [83]3 years ago

7 0

N + D = 55 coins (1) (N stands for nickels, 5N + 10D = 390 cents (2) D stands for dimes) Simplify (2) by canceling the factor 5 in both sides: N + 2D = 78 (3) Subtract eq(1) from eq(3). You will get D = 78 - 55 = 23. Answer. 23 dimes and 55-23 = 32 nickels. Check. 23*10 + 32*5 = 390 cent

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A fruit company delivers its fruit in two types of boxes: large and small. A delivery of 3 large boxes and 5 small boxes has a t

Kaylis [27]

Answer:

Step-by-step explanation:

We need a system of equations here. The first equation is that 3L boxes + 5s boxes (L = large and s = small) = 88 kg so

3L + 5s = 88

12L + 2s = 235 according to the other information given.

Solve the first equation for either L or s. I'll solve for L, just because:

3L = 88 - 5s and

L = $\frac{88}{3}-\frac{5}{3}s$ and sub that into the second equation for L:

$12(\frac{88}{3}-\frac{5}{3}s)+2s=235$ and if you distribute the 12 into the parenthesis you'll simplify it down a bit to

352 - 20s + 2s = 235 and combine like terms:

-18s= -117 so

s = 6.5 kg and plug that in to solve for L:

L = $\frac{88}{3}-\frac{5}{3}(6.5)$ and

L = 18.5 kg

3 0

3 years ago

Find the value of x.

skelet666 [1.2K]

Answer:

x=17

Step-by-step explanation:

6x+33+45=180

6x+78=180

6x=102

x=17

7 0

3 years ago

Read 2 more answers

What is 123% of $938.55?<br><br> Round your answer to the nearest cent

ollegr [7]

Answer:

1154.41 (rounded)

Step-by-step explanation:

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3 years ago

a rectangle is 8cm longer then it is wide, and it’s area is 153cm^2. Find the dimensions of the rectangle.

Stolb23 [73]

Answer:

Width of 9cm and length of 17cm.

Step-by-step explanation:

To calculate an area of a rectangle, use the formula A=l*w. We know the length is 8cm longer than the width. So l = 8 + w. So the area is A= (8+w)*w.

We also know the area is 153. Substitute this value for A and solve.

$153 = (8+w)(w)\\153 = 8w+w^2\\w^2+8w-153 = 0$

To solve the quadratic, use the quadratic formula:

$\frac{-b+/-\sqrt{b^2-4ac} }{2a}$

Here a=1, b=8 and c=-153.

$w=\frac{-b+/-\sqrt{b^2-4ac} }{2a} \\w=\frac{-8+/-\sqrt{8^2-4(1)(-153)} }{2(1)} \\w=\frac{-8+/-\sqrt{64+612} }{2} \\w=\frac{-8+/-\sqrt{676} }{2} \\w=\frac{-8+/-26 }{2} \\w=\frac{-8+26 }{2}=\frac{18}{2}=9 \\and\\w=\frac{-8-26 }{2} =\frac{-34}{2}=-17$

Since w=9 or w=-17, substitute this value for w in l= 8+w to find l.

l = 8+9 = 17

l=8+-17 = -9

Since length cannot be positive, it must be l=17 and w=9.

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3 years ago

Combine like terms y+4+5(y+8)

mote1985 [20]

Answer:

6y+44

Step-by-step explanation:

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3 years ago