Let x be the number of birds observed on Tuesday that would make the ratio between Thursday and Tuesday the same.
The original ratio between Thursday and Tuesday is 80/60 = 4/3
After decreasing the number of birds observed on Thursday by 20, the new number of birds observed on Thursday is 80 - 20 = 60.
The new ratio between Thursday and Tuesday should be 60/x.
Setting up the proportion:
(60/x) = 4/3
Cross multiplying:
3 * 60 = 4 * x
180 = 4x
x = 45
Therefore, Ronnie's aunt would expect to see 45 fewer birds on Tuesday to keep the ratio between the birds seen on Thursday and on Tuesday the same.
Tuesday:60 Wenseday:40 Thursday:80 Friday:100
If the number of birds observed on Thursday decreases by 20, how many fewer birds would Ronnie’s aunt expect to see on Tuesday to keep the ratio between the birds seen on Thursday and on Tuesday the same?
Set up, solve, and explain a proportion.
30 fewer birds; because the number of birds seen on Tuesday should decrease to 30. The current number of birds seen on Tuesday is 40. There should be 10 fewer birds observed to keep the ratio the same.
27 fewer birds; because the number of birds seen on Tuesday should decrease to 27. The current number of birds seen on Tuesday is 40. There should be 13 fewer birds observed to keep the ratio the same.
45 fewer birds; because the number of birds seen on Tuesday should decrease to 45. The current number of birds seen on Tuesday is 60. There should be 15 fewer birds observed to keep the ratio the same.
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