[Ans] (D)
[Question] The speed of a boat in upstream is 60 kmph and the speed of the boat downstream is 100 kmph. Find the speed of the boat in still water and the speed of the stream?
Options:
(A) 70, 10 kmph
(B) 35, 27 kmph
(C) 50, 60 kmph
(D) 80, 20 kmph
(E) 45, 65 kmph
[CoT] Speed of the boat in still water = (60+100)/2 = 80 kmph. Speed of the stream = (100-60)/2 = 20 kmph

[Ans] (B)
[Question] If Friday occurred on 21th January 2005. What was the day of the week on 21th January 2004?
Options:
(A) Sunday
(B) Wednesday
(C) Friday
(D) Monday
(E) Tuesday
[CoT] There are 2 odd days in the year 2004
So, the day on 21th January 2005 will be two days beyond the day on 21th January 2004
On 21th January 2004, it was Wednesday

[Ans] (B)
[Question]

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
How many ways can six girls be selected from a group of ten girls?
Options:
(A) ⁶C₄
(B) ¹⁰C₄
(C) 4C₄
(D) ¹⁰P₄
(E) ¹⁰P₅
[CoT] Six members can be selected from ten members in
¹⁰C₆ = ¹⁰C₄ ways