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3 years ago

The cost for 7 dance lessons is 82$. The cost for 11 lessons is 122$. Write and solve an equation to find the cost of 4 lessons

Mathematics

1 answer:

Juliette [100K]3 years ago

6 0

Answer:

$52

Step-by-step explanation:

Using the equation

y=mx+c

82=7x+c

122=11x+c

11x-7x=122-82

4x=40

x=10

To get c

82=7(10)+c

82-70=c

c=12

For 4 lessons

y=10(4)+12=52

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aksik [14]

Answer:

3/40 = 7.5%

Step-by-step explanation:

3/40 percent error.

3/40 = 7.5%

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3 years ago

Find the unit rate 6 and 2/5 revolutions in 2 and 2/3 in seconds

Makovka662 [10]

Step 1

Convert mixed fractions into fractions

6 2/5 = (6*5)+2) / 5 = 32/5

2 2/3 = (2*3)+2) / 3 = 8/3

Step 2

32/5 ÷ 8 / 3 ; where 32/5 is the 1st fraction and 8/3 is the 2nd fraction

Step 2 (A)

Get the reciprocal of the 2nd fraction:

From 8/3 to 3/8

Step 2 (B)

Multiply 1st fraction to the reciprocal of the 2nd fraction

32/5 * 3/8 = (32*3) / (5*8) = 96/40

Step 2 (C)

Simplify the fraction

96/40 divide by 4 will become 24/10

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3 0

3 years ago

Please answer. Thank you.

Aloiza [94]

Answer:

Step-by-step explanation:

Graph shows constant change between the weight and the cost.

3/2.25 is 1.33333333

4/3 is 1.3333333

5/3.75 is 1.3333333 as well.

Others are not constant.

8 0

3 years ago

One of the loudest sounds in recent history was that made by the explosion of Krakatoa on August 26-27, 1883. According to barom

liraira [26]

Answer:

150.51 dB

Step-by-step explanation:

Data provided in the question:

decibel level of sound at 161 km distance = 180 dB

d₁ = 161 km

d₂ = 4800 km

I₁ = 180 db

The formula for intensity of sound is given as:

I = $10\log(\frac{I_2}{I_1})$

and the relation between intensity and distance is given as:

I ∝ $\frac{1}{d^2}$

Id² = constant

thus,

I₁d₁² = I₂d₂²

$\frac{I_2}{I_1}=\frac{d_1}{d_2}$

therefore,

I = $10\log(\frac{d_1}{d_2})^2$

I = $10\times2\times\log(\frac{161}{4,800})$

I = 20 × (-1.474)

I = -29.49

Therefore,

the decibel level on Rodriguez Island, 4,800 km away

= 180 - 29.49

= 150.51 dB

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3 years ago

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Rom4ik [11]

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3 years ago