MathProblemSolver101

Let Gabriela be G.

We know that in 45 years plus her current age she will be 4 times as old as now, so 45+G=4G.

If we subtract both sides by G, we get 3G=45 and then divide by 3 so her current age is 15.

-MPS101

Answer: Step-by-step explanation: From the measure of the length of the sides of the triangle, 9, 40 and 41 we can infer that the triangle is a right angled triangle. 9-40-41 is a Pythagorean triplet. In a right angled triangle, the circumradius is half the hypotenuse. In the given triangle, the hypotenuse = 41. Therefore, the circumradius is 41÷2= 20.5 units.

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20% of $15 is \(\frac{1}{5} \cdot 15 = $3\) tip. 15%= \(\frac{3}{20}\). \(\frac{3}{20} x = 3\Rightarrow \frac{1}{20} x = 1\Rightarrow x=20\)

Liam's dinner cost $20.

-MPS101

Set the other cyclist's speed as x miles per hour. Therefore the slower cyclist's speed is x-8. Their total distance apart each hour is x+x-8=2x-8. Therefore after 4 hours, their speed is 4(2x-8) which is 8x-32. We can set an equation: \(8x-32=144\) since they are 144 miles apart after 4 hours. We add 32 to both sides and divide by 8 into both sides, and we get x= 22mph for the faster bicyclist and 22-8=14 mph for the slower bicyclist.

Answer:

22 mph for faster bicyclist

14 mph for slower bicyclist

-MPS101

P.S. That speed is FAST! I mean, 22mph? How tiring would that be for FOUR hours! 

lol.

just add all equations. You will get 2A+2B+2C=60

so A+B+C=60/2 = 30

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