Answer:
Which graph's shaded region represents the possible combinations of coffee and tea for this order?
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.
_____
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.
Answer:
C
Step-by-step explanation:
The first equation has to be the ratio of raisins to sunflower seeds. If r is raisins and p is sunflower seeds and there are 3 times as many raisins as sunflower seeds then the first equation must be 3r=p
The second equation should model the prices properly. Raisins are 1.5 per pound and sunflower seeds are 4 per pound, because of this we should have 1.5r (r being each pound of raisins) and 4p (p being each pound of sunflower seeds). From this we know the second equation must be 4p+1.5r=34