I need step-by-step explanation.
I thought I was good in math back when the continents were forming. But it must have just been a dream I had. Because I worked it out in a simplified manner before I read the explanation in the lower section. And I haven’t the slightest clue why (b) is the correct ratio? Hahaha
As soon as I saw the age difference; I thought ‘3 times older’? Ok; dad is 30; kid is 10.
Ten years later; dad is 40; kid is 20.
Ratio of current age is 2 to 1.
Sorry; I guess I just don’t understand the question🤔
There must be other applications of ratio that I am just not aware of?
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@yoyodoc funny answer.
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Let the current age of the father be x
and the current age of the son y
10 years ago the age of the father was x - 10
and the age of the son was y - 10
At that point the father is three times as old was the son
which means that three times the son’s age equals the fathers age.
x - 10 = 3(y - 10)
in ten year time the father will be x + 10
and the son y + 10
At that point the father will twice as old as the son, or twice the son’s age will equal the father’s age
x + 10 = 2(y + 10)
Now solve that two equations and you will get the current ages.
Hope this helps!
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The dad is 70 now and the kid is 30 now. (7 : 3)
Ten years ago the dad was 60 and the kid was 20. (3 : 1)
Ten years from now the dad will be 80 and the kid will be 40 (2 : 1)
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Ok i will try solving both the equations.
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i got x=5y-10/2 by solving both equations
but what is the value of x and y?
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You have two equations to solve. First isolate x in both:
x - 10 = 3(y - 10)
x + 10 = 2(y + 10)
x = 3(y - 10) + 10
x = 2(y + 10) - 10
You have two different things that both equal x, so you can put them into the same equation:
3(y - 10) + 10 = 2(y + 10) - 10
Now solve for y:
3y - 30 + 10 = 2y + 20 - 10
3y - 20 = 2y + 10
y - 20 = 10
y = 30
Now substitute 30 for y in one of the x equations:
x = 2(30+10)-10
x = 60 + 20 - 10
x = 70
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how do u do that textbox thing?
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Try the cheatsheet at Markdown Reference or the tutorial there!
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Good Thank you.
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Maybe I will use yoyoexpert forums for math help now! lol, I probably actually will.
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yes I and all others are waiting for your questions.
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Ok… I finally understand it🤓
Right now you guys are 3 times smarter than me. In ten years you will be 4 times smarter than me.
So the ratio in 10 years will be : 1whole brain to 1half brain.
Piece a cake🤡
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i think all it takes is practice and consistency.
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