The problem statement gives a relation between the amount removed from one bag and the amount removed from the other. It asks for the amount remaining in each bag. Thus, there are several choices for variables in this problem, some choices resulting in more complicated equations than others.
Let's do it this way: let x represent the amount remaining in bag 1. Then the amount removed from bag 1 is (100-x). The amount remaining in bag 2 is 2x, so the amount removed from that bag is (100-2x). The problem statement tells us the relationship between amounts removed:
... (100 -x) = 3(100 -2x)
... 100 -x -3(100 -2x) = 0 . . . . . . subtract the right side
... 5x -200 = 0 . . . . . . . . . . . . . . eliminate parentheses and collect terms
... x -40 = 0 . . . . . . . . . . . . . . . . .divide by 5
... x = 40 . . . . . . . . . . . . . . . . . . . add 40
- 40 kg is left in the first bag
- 80 kg is left in the second bag
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<u>Check</u>
The amount removed from the first bag is 60 kg. The amount removed from the second is 20 kg. The amount removed from the first bag is 3 times the amount removed from the second bag, as described.
I am assuming theres an addition sign between the 3 and 4.
So basically you want to multiply the 5x by both terms so it will end up being
(5x•3) + (5x•4)
Now simplify:
15x+20x
Hope this helped ^_^
QUESTION 1
When the plane reaches an altitude of 360,000 feet, the temperature outside the plane is 65 degrees below zero Fahrenheit.
This means that the temperature will be:

The temperature is -65°F.
QUESTION 2
If the temperature gets warmer by 10 degrees, this means that the new temperature will be the sum of the original temperature and 10 degrees:

The temperature is -55°F.
Trigonometry would help with this question.
The area of a regular hexagon is ((3√3)s^2)/2 where s is the side.
Plugging in 2 gives us 6√3 or 10.39 feet.