A team has to design a flag. The team has four yellow strips of cloth and five green strips of cloth that they must use as is to make the flag. How many different flags can the team design with the materials at hand?
Answers.
A) 24  B) 120  C) 126  D) 140  E) 156
The # of permutations of total 4+5= 
<gadget id="calculator">4+5</gadget>
<output>9</output>
9 strips where 4 are identical yellow and 5 are identical green is 9!/(4!*5!)=126 (note that they must use all the materials at hand, also I guess that the strips must be either only vertical or only horizontal).   Answer: 126.
<result>C</result>
A team has to design a flag. The team has four yellow strips of cloth and five green strips of cloth that they must use as is to make the flag. How many different flags can the team design with the materials at hand?