Rationale: Since average price of a pencil = 2
∴ Price of 75 pencils = 150
∴ Price of 30 pens = (570 – 150) = 360
∴ Average price of a pen = 420⁄60 = 14
The answer: (E)
Question: 30 pens and 75 pencils were purchased for 570. If the average price of a pencil was 2.00, find the average price of a pen.
Options:
(A) 10
(B) 11
(C) 12
(D) 13
(E) 14
Reasoning: Total members in the group = 7
Average amount = Rs. 30
Total amount with them = 7 * 30 = Rs. 210
One number has Rs. 70. So, the amount with remaining 6 people = 210 - 70 = Rs. 140
The average amount with them = 140/6 = Rs. 70/3
Ans: (B)
Question: The average amount with a group of seven numbers is Rs. 30. If the newly joined member has Rs. 70 with him, what was the average amount with the group before his joining the group?
Options:
(A) s. 25.6
(B) s. 70/3
(C) s. 16.6
(D) s. 26/3
(E) s. 25
Rationale: The other parts are equal to xy2 – x2y + 2x2y2.
The answer: (B)
Question: Four of the following five parts numbered (a), (b), (c), (d) and (e) in the following equation are exactly equal. Which of the parts is not equal to the other four? The number of that part is the answer.
Options:
(A) xy2 – x2y + 2x2y2
(B) xy2(1 – 2x)  + x2y(2y – 1) 
(C) xy2(1 + x)  – x2y(1 – y) 
(D) xy[y(1 + x)  – x(1 – y) ]
(E) xy(y – x + 2xy) 
Reasoning: Since the weight age of eighth examination is not known, hence can not be determine
Ans: (D)
Question: Sumitra has an average of 56% on her first 7 examinations. How much should she make on her eighth examination to obtain an average of 60% on 8 examinations?
Options:
(A) 88%
(B) 78%
(C) 98%
(D) Cannot be determined
(E) None of these
Rationale: 9 is divisible by 3. So, it is not a prime number.
The answer: (D)
Question: Which one of the following is not a prime number?
Options:
(A) 2
(B) 3
(C) 5
(D) 9
(E) 7
Rationale: Total # of codes possible is 3*3*3 = 27. Oit of those 27 codes only the product of 555 will be odd, the remaining 26 will have either 2 or 4 in them, which ensures that their product will be even. Therefore the number of codes where the product of the digits is even = (total) - (restriction) = 27 - 26 = 1.
The answer: (D)

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.
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Question: A telephone company needs to create a set of 3-digit area codes. The company is entitled to use only digits 2, 4 and 5, which can be repeated. If the product of the digits in the area code must be odd, how many different codes can be created?
Options:
(A) 20
(B) 22
(C) 24
(D) 1
(E) 30