GRE Math Problem 42

If 3^a=b and 3^c=d, then bd=
(A) 3^ac
(B) 3^a+c
(C) 6^a+c
(D) 9^ac
(E) 9^a+c


Solution for GRE Math Problem 41:
Let’s build this sequence: 1, 1x3-1=2, 2x3-1=5, 5x3-1=14, 14x3-1=41, 41x3-1=122 – this is the smallest term greater than 100. It is greater than 120
Answer:A

GRE Math Problem 41

The first term of a sequence is 1. Starting with the second term, each term is 1 less than 3 times the previous term.

Column A	Column B
The smallest number greater than 100 in the sequence	120

Solution for GRE Math Problem 40:

As we can see, the sum of the areas of two equilateral triangles whose sides are 10 is twice less than the area of one equilateral triangle whose sides are 20


Answer:B

GRE Math Problem 40

Column A	Column B
The sum of the areas of two equilateral triangles whose sides are 10	The area of one equilateral triangle whose sides are 20

Solution for GRE Math Problem 39:
If x was 90, AB would be a hypotenuse in the right isosceles triangle and its value would be .
And for x > 90, AB will be even longer.
Answer: A

GRE Math Problem 39

x>90

Column A	Column B
The length of AB	7

Solution for GRE Math Problem 38:
How many three-digit numbers are?
The first digit can be any of 9, the second - any of 10, so does the third. Total 9x10x10=900 combinations.

How many three-digit palindromes are?
The first digit can be any of 9, the second - any of 10, and the third one must be exactly the same as the first, thus, leaving only 1 possibility. Total 9x10x1=90.

The probability that a three-digit number chosen at random is a palindrome is 90x900=0.1
Answer: C

GRE Math Problem 38

A number is a palindrome if it reads exactly the same from right to left as it does from left to right.
For example, 959 and 24742 are palindromes.

Column A	Column B
The probability that a three-digit number chosen at random is a palindrome	0.1

Solution for GRE Math Problem 37:
If all 16 shirts had costed $10, total amount of money spent would have been $160. It is $27 less, than the actual amount. Since Each $13 shirt is $3 more expensive than $10 shirt, there were 9 $13 shirts and 7 $10 shirts
Answer: A

GRE Math Problem 37

A man buys 16 shirts. Some of them cost $13 each, while the remainder cost $10 each. The cost of all 16 shirts is $187.

Column A	Column B
The number of $13 shifts purchased	The number of $10 shirts purchased

Solution for GRE Math Problem 36:

If all the tickets hab been sold for $25, the total sum would be 25x11=$275, which is 275-227=.$48 less, than the actual amount of money. Since the $13 ticket is 25-13=$12 cheaper, theree were = 4 tickets for $13 and 11-4=7 tickets for $25.
 Answer: Column A is bigger

GRE Math Problem 36

Tickets to a concert cost $25 and $13. An agent sells 11 tickets for a total price of $227.

Column A	Column B
The number of $25 tickets sold	The number of $13 tickets sold

Solution for GRE Math Problem 35:
If a²=b, then .
Now, if a=1, then Column A = 2 > Column B = 1.
And if  a=2, then Column A = 1 < Column B = 4.
Answer: D, unable to define.