question: How many two-digit numbers satisfy this property.: The last digit (unit's digit) of the square of the two-digit number is 7 ?
Options:
(A) 3
(B) 1
(C) 4
(D) 0
(E) 2
answer: Stream of consciousness: A number ending with 7 can never be a perfect square. The answer is (D).


q: A family pays $850 per year for an insurance plan that pays 80 percent of the first $1,000 in expenses and 100 percent of all medical expenses thereafter. In any given year, the total amount paid by the family will equal the amount paid by the plan when the family's medical expenses total.
Options:
(A) $1,000
(B) $1,250
(C) $1,400
(D) $1,800
(E) $2,200
a: Stream of consciousness: Upfront payment for insurance plan = 850$
Family needs to pay 20 % of first 1000 $ in expense = 200$
Total amount paid by family when medical expenses are equal to or greater than 1000 $ = 850 + 200 = 1050 $
Total amount paid by insurance plan for first 1000 $ = 850 $
Total amount paid by family will equal amount paid by plan when medical expense = 1250 $
(Since insurance plan will pay 100% of amount that exceeds 1050$ ) The answer is (B).


question: A computer factory produces 4032 computers per month at a constant rate, how many computers are built every 30 minutes assuming that there are 28 days in one month?
Options:
(A) 2.25.
(B) 3.00.
(C) 4.5.
(D) 5.225.
(E) 6.25.
answer: Stream of consciousness: Number of hours in 28 days = 28*24
Number of 30 mins in 28 days = 28*24*2
Number of computers built every 30 mins = 4032/( 28*24*2) = 3 The answer is (B).


q: When N is divided by 10 the remainder is 1 and when N is divided by 3 the remainder is 2. What is the remainder S when N is divided by 30?
Options:
(A) (a)  4
(B) (b)  7
(C) (c)  11
(D) (d)  13
(E) (e)  17
a: Stream of consciousness: N ends in the digit 1 because when N is divided by 10, the remainder is 1. Since N ends in 1, the remainder S when N is divided by 30 also ends in a 1. 11 is the only choice which ends in a 1. The answer is (C).


question: A goods train runs at the speed of 72 km/hr and crosses a 250 m long platform in 26 sec. What is the length of the goods train?
Options:
(A) 49 sec
(B) 50 sec
(C) 48 second
(D) 43 sec
(E) 32 sec
answer: Stream of consciousness: D = 540 + 180 = 720
S = 54 * 5/18 = 15 mps
T = 720/15 = 48 se The answer is (C).


question: The average mark obtained by 22 candidates in an examination is 46. The average of the first ten is 55 while the last eleven is 40 .The marks obtained by the 11th candidate is ?
Options:
(A) 22
(B) 0
(C) 19
(D) 18
(E) 16
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: It is clear that 22 x 46 = 10 x 55 + K + 11 x 40 ⇒⇒ K = 22 The answer is (A).