q: A certain car uses 12 gallons of gasoline in traveling 300 miles. In order for the car to travel the same distance using 10 gallons of gasoline, by how many miles per gallon must the car's gas mileage be increased?
Options:
(A) 2
(B) 4
(C) 5
(D) 8
(E) 10
a: 300/10 = 30. The difference is 30 - 25 = 5. The answer is (C).
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q: In a class, the average age of 45 boys is 10 years and the average of 15 girls is 10 years. what is the average age of the whole class?
Options:
(A) 12 Years
(B) 12.3 Years
(C) 10 Years
(D) 13 Years
(E) 15 Years
a: Total age of 60 students
(45X 10+15 X 10) = 630
Average = 600/60 = 10 Years The answer is (C).
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q: Given a two-digit number, the unit's digit exceeds its ten's digit by 5 and the product of the given number and the sum of its digits is equal to 90, which of the options is the number?
Options:
(A) 27
(B) 16
(C) 38
(D) 61
(E) 83
a: Using the elimination method the option that fits this description is 27
7-2 = 5 (unit's digit that exceeds its ten's digit by 3)
27*9 = 243 (the product of the given number and the sum of its digits is equal to 175) The answer is (A).
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q: The sale price sarees listed for Rs.400 after successive discount is 10% and 5% is?
Options:
(A) 345
(B) 340
(C) 342
(D) 346
(E) 341
a:
400*(90/100)*(95/100) = 342 The answer is (C).
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