The left-handed students12% are left handed, percent means per hundred. Change percent into per 100.
12% =

Then simplify the fraction by dividing the numerator and denominator by 4

=

=

This is the fraction showing the proportion of the left-handed students
The right-handed studentsDetermine the fraction showing the proportion of the right-handed students
1 - the left-handed
= 1 -

Equalize the denominator to 25

Simplify

This is the proportion of the right-handed students
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Are there more right-handed or left-handed students?There are more right-handed students than the left-handed students, because 21/25 is more than 3/25</span>
I think in this situation the best method would be a guess and check. You know that there are 8 dimes more than there are nickels. So just keep increasing each number by one until you reach $1.40. If there were 9 dimes and 1 nickels it would add up to $0.95. If there were 10 dimes and 2 nickels, it would add up to $1.10. If there were 11 dimes and 3 nickels, it would add up to $1.25. If there were 12 dimes and 4 nickels, it would add up to $1.40. So your answer is 12 dimes and 4 nickels.
I hope this helped!
(x-3)(x+4). -3,4 multiply to -12, and add to get 1