question: At what rate percent on simple interest will a sum of money double itself in 30 years?
Options:
(A) 3 1/3%
(B) 8 1/3%
(C) 3 5/3%
(D) 5 1/3%
(E) 3 1/7%
answer: Stream of consciousness: P = (P*30*R)/100
R = 3 1/3% The answer is (A).


q: (4300731)-! = 2535618. Find value of !?
Options:
(A) 1213441
(B) 2354546
(C) 4354556
(D) 2435454
(E) 1765113
a: Stream of consciousness: Let 4300731 - ! = 2535618
Then !, = 4300731 - 2535618 = 1765113 The answer is (E).


question: A car traveled from San Diego to San Francisco at an average speed of 54 miles per hour. If the journey back took twice as long, what was the average speed of the trip?
Options:
(A) 24.
(B) 32.
(C) 36.
(D) 42.
(E) 44.
answer: Stream of consciousness: Let the time taken be = x
One way distance = 54x
Total distance traveled = 2 * 54x = 108x
Total time taken = x + 2x = 3x
Average speed = 108x/3x = 36 The answer is (C).


q: Amy, Bob, Cindy, and Daniel all have the same birthday, but they are all different ages. Today is their birthday. Cindy's age is divisible by Bob's age, and Amy's age is divisible by Cindy's age. If A is Amy's age in years, B is Bob's age, and C is Cindy's age, which of the following CANNOT be Daniel's age?
Options:
(A) AC/B
(B) (A+C) /B
(C) (A+B) /C
(D) AB/C
(E) (A-C) /B
a: Stream of consciousness: Since today's is Daniel's birthday, his age must be an integer. As per the question, let A = 12, B = 2, and C = 6. Plugging these into the answer choices, only C does not yield an integer. The answer is (C).


question: If X is the sum of first 100 positive even integers and Y is the sum of first 100 positive odd integers, what is the value of x-y?
Please try to explain your answers
Options:
(A) 0
(B) 25
(C) 50
(D) 75
(E) 100
answer: Stream of consciousness: First even minus first odd = 2-1 = 1;
The sum of first 2 even integers minus the sum of first 2 odd integers = (2+4)-(1+3) = 2;
The sum of first 3 even integers minus the sum of first 3 odd integers = (2+4+6)-(1+3+5) = 3;
We can see the patterns here, so the sum of first 100 positive even integers minus the sum of first 100 positive odd integers will be 100. The answer is (E).


question: Train A & B leave from same station and reaches same destination but train A leaves half an after Train B & travels 2 times faster than B. Total distance is 100 miles & train B travels 50 miles/hour. Which train reaches the destination first & what is the time difference between the train
Options:
(A) Train A reaches 30 minutes before Train B
(B) Train B reaches 30 minutes before Train A
(C) Train A reaches 60 minutes before Train B
(D) Train B reaches 60 minutes before Train A
(E) None of the above
answer:

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
Stream of consciousness: Time taken for train A = 30 minutes + d1/s1 = 30 minutes + 100 / 100 = 1 hours 30 minutes
Since Train B travels 50 miles / hour ; train A travels twice the speed of B which gives s1 = 100 miles/ hour
Time taken for train B = d2/s2 = 100 / 50 = 2 Hours
So Train A reaches 30 minutes before Train B The answer is (A).