Callum and Isabel have a total of 240 stamps. The ratio of the number of Callum's stamps to the number of Isabels's stamps is 3 : 8
Callum buys some stamps from Isabel.
The ratio of the number of Callum's stamps to the number of Isabel's stamps is now 3:2
How many stamps does Callum buy from Isabel?
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Amira is painting a rectangular banner 2 1/4 yards wide. the banner will have a blue background. amira has enough paint to cover 1 1/2 square yards of the wall. the school colors are blue and yellow, so amira wants to add yellow rectangles on the left and right sides of the blue rectangle. the yellow rectangles will each be 3/4 yards wide and the same height as the blue rectangle. what will be the total area of the two yellow rectangles?