The way I do questions like these is to call the unknown number x, and then build an equation using the information given.
So for Q1, let the number be x. Then the true answer is 7x/8 and the wrong answer is 8x/7. These differ by 15/14. So make an equation out of this and solve for x.
If you post your attempt we can move on to the others.
Bob
]]>Question 2: Find the number , one sixth of which exceeds its one-ninth by 654 ?
Question 3 : Divide 600$ among A,B and C so that $40 more than 2/5 of A's share , $20 more than 2/7 of B's Share , $10 more than 9/17 of C's Share may be equal?
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