There r 3 boys & 4 girls; Howmany ways they r arranged such that boys should be always together ?
Choices
A) 120ways B) 220ways C) 420ways D) 720ways E) 520ways
By kept 3boys together(1) and arranging 4 girls with them   5! = 5*4*3*2*1= 
<gadget id="calculator">5*4*3*2*1</gadget>
<output>120</output>
120ways. (i.e., 4+1=5)   Possible arrangements of 3 boys in following ways   3! = 3*2*1= 
<gadget id="calculator">3*2*1</gadget>
<output>6</output>
6ways   Now, arrange all with the boys together     120*6= 
<gadget id="calculator">  120*6</gadget>
<output>720</output>
720ways   ANSWER:720ways
<result>D</result>
There r 3 boys & 4 girls; Howmany ways they r arranged such that boys should be always together ?