Let t represent Todd's age now.
.. 4(t -3) -(t -3) = 81 . . . . . . 3 years ago, their differnce in ages was 81.
.. 3t -9 = 81
.. t = (81 +9)/3 = 30
Todd is 30 now.
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You can also work this by considering "ratio units." 3 years ago, the ratio of their ages was 4:1, a difference of 3. That difference corresponds to 81 years, so each "ratio unit" represents 81/3 = 27 years. Todd's age then was 1 ratio unit, 27 years. Now, Todd's age is 30.
A coefficient is a numerical or constant quantity placed before and multiplying the variable in an algebraic expression (e.g. 4 in 4x).
The 2 and + are out since they don't have variables(and the + is just a +).
So 4 and x are left. x is a variable, not a coefficient, so the last(and correct) answer is 4.
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hope it helps
Answer:
i do not know
Step-by-step explanation:
1) 10 3/10
3) 2 1/2
4) 10 2/3
6) 6 1/2
7) 4 3/4
9) 1 8/9
10) 1 5/6
