1,000 grams = 1 kilogram
2,000 grams = 2 kilograms
3,000 grams = 3 kilograms
4,000 grams = 4 kilograms
5,000 grams = 5 kilograms
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10,000 grams = 10 kilograms
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20,000 grams = 20 kilograms
.
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30,000 grams = 30 kilograms
Answer: To solve one-step equations, we do the inverse (opposite) of whatever operation is being performed on the variable, so we get the variable by itself. The inverse operations are: Addition and subtraction.
hope this helps
If the initial time was 60 seconds and 18 seconds have passed,

There would be 42 seconds left.
11 more than five of a certain number would be written as 5x+11 and it is (means equal to) twenty more than two times that number, which would be 2x+20. So the equation would be
5x+11=2x+20
-2x -2x (get the x's on one side)
3x+11=20
-11 -11 (get the numbers on one side)
3x=9
/3 /3 (divide by 3, so you can get the x by itself)
X=3 (the number is 3)