Question 1206575
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Answer: <font color=red size=4>5</font>



Explanation: There are many ways we can do this problem. I'll discuss two methods shown below.


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Method 1


Focus only on the masons and welders. The other professions are a distraction. 
There are T number of cards to give to these two professions.
Masons get 1/4 of the pile and the welders get the remaining 3/4 of the pile.


In terms of algebra,
T/4 = amount masons get = unknown
(3/4)T = amount welders get = 15


(3/4)T = 15
T = 15*(4/3)
T = 20
There are 20 cards to hand out to masons and welders.


Masons will get <font color=red>5 cards</font> because T/4 = 20/4 = <font color=red>5</font>


Or you can compute it like this: 20-15 = <font color=red>5</font> since welders got 15 cards of the 20 cards for these two professions.


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Method 2


This method is a bit more lengthy. Feel free to skip it if you prefer the first method. But it could be handy to know multiple approaches.


x = total number of cards
x/3 = amount given to carpenters
x - x/3 = 2x/3 = remaining amount after carpenters get their cards
If the carpenters get 1/3 of the cards, then the others get the remaining 2/3 of the cards.


(1/3)*(2x/3) = 2x/9 = amount given to drivers
(2x/3) - (2x/9) = 4x/9 = amount remaining after drivers get their cards
Or you could say,
(2/3)*(2x/3) = 4x/9 = amount remaining after drivers get their cards


(1/4)*(4x/9) = x/9 = amount given to masons
(4x/9) - (x/9) = 3x/9 = x/3 = amount remaining after giving cards to masons
Or,
(3/4)*(4x/9) = x/3 = amount remaining after giving cards to masons


x/3 = amount given to welders
x/3 = 15
x = 3*15
x = 45 is the total number of cards


x/9 = 45/9 = <font color=red>5</font> cards were given to masons 
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