Answer:
d
Step-by-step explanation:
I THINK
Answer:
38 miles
Step-by-step explanation:
Given,
The speed of Doreen = 9 miles per hour,
Since,
![Speed = \frac{Distance}{Time}\implies Distance = Speed\times Time](https://tex.z-dn.net/?f=Speed%20%3D%20%5Cfrac%7BDistance%7D%7BTime%7D%5Cimplies%20Distance%20%3D%20Speed%5Ctimes%20Time)
So, the distance covered by Doreen in 2 hours = 9 × 2 = 18 miles,
∵ Doreen speed is 90% of Irena's speed.
I.e. 90% of Irana's speed = 9 miles per hour
![\implies \frac{90}{100}\times \text{ Irana's speed}=9](https://tex.z-dn.net/?f=%5Cimplies%20%5Cfrac%7B90%7D%7B100%7D%5Ctimes%20%5Ctext%7B%20Irana%27s%20speed%7D%3D9)
,
Thus, the distance covered by Irana in 2 hours = 10 × 2 = 20 miles
Hence, the distance between their houses = distance covered by Doreen in 2 hours + distance covered by Irana in 2 hours
= 18 + 20
= 38 miles
They have to be straight line objects with no curves
Answer:
350
Step-by-step explanation:
The solution to the equation can be found by multiplying by the denominator, then dividing by its coefficient.
![0.22 = \dfrac{77}{x}\qquad\text{given}\\\\0.22x = 77\qquad\text{multiply by $x$}\\\\x=\dfrac{77}{0.22}=350\qquad\text{divide by the coefficient of x}](https://tex.z-dn.net/?f=0.22%20%3D%20%5Cdfrac%7B77%7D%7Bx%7D%5Cqquad%5Ctext%7Bgiven%7D%5C%5C%5C%5C0.22x%20%3D%2077%5Cqquad%5Ctext%7Bmultiply%20by%20%24x%24%7D%5C%5C%5C%5Cx%3D%5Cdfrac%7B77%7D%7B0.22%7D%3D350%5Cqquad%5Ctext%7Bdivide%20by%20the%20coefficient%20of%20x%7D)
The missing value in the fraction is 350.
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<em>Additional comment</em>
Here, we have rewritten the percentage as a decimal fraction. You could also rewrite it as a ratio of two integer: 22% = 22/100. Sometimes there is confusion about percentages. It can help to think of the % symbol as meaning /100:
22% = 22/100
Of course, that is "twenty-two hundredths" or 0.22.
If you just write the problem using 22/100 for 22%, then you get the proportion ...
22/100 = 77/x
22x = 7700 . . . . . "cross multiply" (multiply by 100x)
x = 7700/22 = 350 . . . . divide by the coefficient of x
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If you're paying attention, you see that the solution of this kind of equation has the appearance that the denominator variable and the left-side value are simply swapped:
![0.22 = \dfrac{77}{x}\ \leftrightarrow\ x=\dfrac{77}{0.22}](https://tex.z-dn.net/?f=0.22%20%3D%20%5Cdfrac%7B77%7D%7Bx%7D%5C%20%5Cleftrightarrow%5C%20x%3D%5Cdfrac%7B77%7D%7B0.22%7D)
Effectively, we have multiplied both sides of the equation on the left by x/0.22. There is a <em>property of equality</em> that lets us do that. There is no such thing as a property of equality that says "swap with denominator." You must always pay attention to what is allowed by the properties of equality.