Forming formulae and equations Watch
Tony also has 18 sweets
Sue gives tony x sweets
Sue then eats 5 of her sweets
Tony then eats half of his sweets
Write expressions for the number of sweets sue and tony now have
What happens with the number of Sue's sweets when she gives them to Tony and vice versa what to Tony's sweets when he gets them from her?
What happens with Sue's sweets when she eats five of the remained them and to Tony's when he eats the half?
If you need help, look in the spoiler!
At the beginning, both Sue and Tony have 18 sweets:
18 = 18
Then Sue gives x from her sweets to Tony. That means Sue's sweets is reduced by x and Tony's ones enhanced by the same value, namely x:
18 - x = 18 + x
After that Sue eats five of her remained sweets, that is to say the sweets are reduced by 5:
18 - x - 5 = 13 - x (Sue's term)
Analogous, Tony eats the half of his entire sweets:
0,5*(18 + x) = 9 - 0,5x (Tony's term)
Your equation is:
13 - x = 9 - 0,5x
Solved to x, you get x = 8
Put in the equation, it is true:
13 - 8 = 9 - 0,5*8
5 = 5
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