DAT Missed Exam Questions Correctly
Answered & Verified.
Currently, Tommy is five times as old as Bianca. In eight years, Tommy will only be three times as old as
Bianca. How old is Tommy right now?
A. 8
B. 16
C. 24
D. 32
E. 40 - CORRECT ANSWER Answer: E. 40
This is a question involving the ratio of ages. To solve this question, we should first start by writing an
equation with the information given. Let the ages of Tommy and Bianca in the present be T and B
respectively.
STEP 1: Let:
T = 5B
T + 8 = 3 (B+8)
STEP 2: We can substitute T with 5B since the two variables are equal, to create:
5B + 8 = 3 (B + 8)
STEP 3: Finally, we can expand and solve:
5B + 8 = 3B + 24
2B = 16
B=8
T = 5B = 5 x 8 = 40
Therefore, Tommy is currently 40-years old
A sock drawer contains 7 pairs of red socks, 4 pairs of blue socks and 2 pairs of yellow socks. What is the
probability that two socks selected at random, without replacement, are both red?
, A. 1/4
B. 7/25
C. 49/169
D. 7/26
E. 5/12 - CORRECT ANSWER B. 7/25
To solve this problem, we must first correctly identify it as a probability problem without replacement.
Also, note that the amount of socks is given in pairs, but the socks that are drawn are individual.
STEP 1: Firstly, we should figure out the total number of socks:
26 socks total
STEP 2: The probability of drawing both red socks is the probability of first drawing a red sock multiplied
by the probability of drawing a second red sock, accounting for the lack of replacement.
14 red socks/26 socks X 13 remaining red socks/25 remaining socks
7/13 x 13/25 = 7/25
If a 4L solution is 80% concentrated lime juice and 20% water, how much 30% concentrated lime juice
must be added so that the concentration of the resulting solution is 50% concentrated lime juice?
A. 3L
B. 4L
C. 6L
D. 8L
E. 10L - CORRECT ANSWER C. 6L
STEP 1: First, let's see how much lime juice exists in the 4L solution:
STEP 2: The question wants to know how much 30% concentrated lime juice we can add to reach a total
final concentration of 50%. That means we want to set up an equation to solve as follows:
We can rewrite 50% as 1/2.
Answered & Verified.
Currently, Tommy is five times as old as Bianca. In eight years, Tommy will only be three times as old as
Bianca. How old is Tommy right now?
A. 8
B. 16
C. 24
D. 32
E. 40 - CORRECT ANSWER Answer: E. 40
This is a question involving the ratio of ages. To solve this question, we should first start by writing an
equation with the information given. Let the ages of Tommy and Bianca in the present be T and B
respectively.
STEP 1: Let:
T = 5B
T + 8 = 3 (B+8)
STEP 2: We can substitute T with 5B since the two variables are equal, to create:
5B + 8 = 3 (B + 8)
STEP 3: Finally, we can expand and solve:
5B + 8 = 3B + 24
2B = 16
B=8
T = 5B = 5 x 8 = 40
Therefore, Tommy is currently 40-years old
A sock drawer contains 7 pairs of red socks, 4 pairs of blue socks and 2 pairs of yellow socks. What is the
probability that two socks selected at random, without replacement, are both red?
, A. 1/4
B. 7/25
C. 49/169
D. 7/26
E. 5/12 - CORRECT ANSWER B. 7/25
To solve this problem, we must first correctly identify it as a probability problem without replacement.
Also, note that the amount of socks is given in pairs, but the socks that are drawn are individual.
STEP 1: Firstly, we should figure out the total number of socks:
26 socks total
STEP 2: The probability of drawing both red socks is the probability of first drawing a red sock multiplied
by the probability of drawing a second red sock, accounting for the lack of replacement.
14 red socks/26 socks X 13 remaining red socks/25 remaining socks
7/13 x 13/25 = 7/25
If a 4L solution is 80% concentrated lime juice and 20% water, how much 30% concentrated lime juice
must be added so that the concentration of the resulting solution is 50% concentrated lime juice?
A. 3L
B. 4L
C. 6L
D. 8L
E. 10L - CORRECT ANSWER C. 6L
STEP 1: First, let's see how much lime juice exists in the 4L solution:
STEP 2: The question wants to know how much 30% concentrated lime juice we can add to reach a total
final concentration of 50%. That means we want to set up an equation to solve as follows:
We can rewrite 50% as 1/2.
