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MC-IIA Questions

 
 
zhengEddy的头像
MC-IIA Questions
zhengEddy 发表于 2019年01月12日 Saturday 16:18
 

Hi, I am not sure on how to do questions 5.28 and 5.29, and I do not know how to finish 3.27 after putting the 6 red balls in place. Thanks!

 
ReynosoDavid的头像
Re: MC-IIA Questions
ReynosoDavid 发表于 2019年01月14日 Monday 11:05
 

For 5.28 try using complementary counting (proceed similar to example 5.8). To count how many ways are there to sum to $200$ with repeated digits consider cases: all numbers repeated and two numbers repeated.

For 5.29, proceed similar to example 5.9. Note $40 = 2^3 \times 5$. So any factor of $40$ is of the form $2^a \times 5^b$. Consider three factors of this form and multiply them so they equal $40$. What can you say about the exponents of the numbers?

For 5.27 pretend for a second that all black cards are identical. How would you proceed? Once you find the answer to the problem pretending all black cards are identical, arrange the black cards in some order and arrange them with the red cards as you did before.