GRE Permutation 2 questions - Rearranging boys girls; Rearranging white balls, black balls

Video solution to 2 questions that were posted as part of solution to Q5 of Wizako's Permutation Probability Chapter Test.
These 2 questions are to be solved using the same approach as we used for Q5.
Question 1
In how many ways can 3 boys and 3 girls be made to stand in a line such that no two boys stand together?
Question 2
In how many ways can 10 balls, 4 which are black and identical and 6 of which are white and identical be arranged in a line such that no two black balls are placed next to each other?
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[@fairylishan1500]

Can this type of question "In how many ways can the word COMPUTER be arranged such that vowels doesn't come together" be solved like in the video?

[@sarojkhatiwada6224]

and why cant the arrangemant begin for boys...shouldnt we multiply the answer by 2 at the last?

[@WizakoPrepGRE]

Hi Saroj, The arrangements beginning with a boy, etc. would all be taken care of in our approach. This is why we have 4 places for boys as compared to only 3 fixed places for girls.