Think of a NumberTen students think of a number then perform various operations on that number. You have to find what the original numbers were. 
This is level 3: Negative decimal THOAN problems. You can earn a trophy if you get at least 7 questions correct.
InstructionsTry your best to answer the questions above. Type your answers into the boxes provided leaving no spaces. As you work through the exercise regularly click the "check" button. If you have any wrong answers, do your best to do corrections but if there is anything you don't understand, please ask your teacher for help. When you have got all of the questions correct you may want to print out this page and paste it into your exercise book. If you keep your work in an ePortfolio you could take a screen shot of your answers and paste that into your Maths file. 



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Level 1  Whole number THOAN problems
Level 2  Decimal THOAN problems
Level 3  Negative decimal THOAN problems
Daniel says 'If I double my number and add 6 the answer is 30'
Start at the end of the sentence with the answer 30 and undo all of the operations Daniel performed on his number in reverse order.
30 minus 6 then divide by two
The number Daniel was thinking about was 12
Let the number that Daniel is first thinking of be n.
2n + 6 = 30
Subtract 6 from both sides
2n = 24
Divide both sides by 2
n = 12
The number Daniel was thinking about was 12
Don't wait until you have finished the exercise before you click on the 'Check' button. Click it often as you work through the questions to see if you are answering them correctly. You can doubleclick the 'Check' button to make it float at the bottom of your screen.
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