Try the following GMAT Problem Solving question on finding terms of a general sequence.

Question 48:

In a sequence each term after the first term is one less than twice the previous term. If the third term of the sequence is $t$, then what is the first term expressed in terms of $t$ ?

1. $\quad 2t-1$

2. $\quad \dfrac{t+1}{2}$

3. $\quad \dfrac{t+1}{4}$

4. $\quad \dfrac{t-3}{4}$

5. $\quad \dfrac{t+3}{4}$

 
Try the following GMAT Problem Solving question on the properties of right triangles that are commonly tested on the GMAT.

Question 47:

In the figure below, the perimeter of triangle $BDC$ exceeds the perimeter of triangle $ABD$ by how much?

1. $\quad 2\sqrt{3}$

2. $\quad 4$

3. $\quad 3\sqrt{3}$

4. $\quad 6$

5. $\quad 4\sqrt{3}$

 
Try the following GMAT data sufficiency question that tests your understanding of finding lengths of line segments in a circle.

Question 46:

In the semicircle shown below with center $O$, the length of $OA$ is $8$. What is the length of line segment $AB$ ?

1. (1) The area of the semicircle is $200 \pi$.
2. (2) $OC=16$ and $CD=12$.

1. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
2. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
3. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
4. EACH statement ALONE is sufficient.
5. Statements (1) and (2) TOGETHER are NOT sufficient.

 
The following GMAT data sufficiency question tests your understanding of applying distance, rate, and time relationships to problems tested on the GMAT.

Question 45:

Trains $A$ and $B$ left stations $R$ and $S$ simultaneously on two separate parallel rail tracks that are $350$ miles long. The trains passed each other at point $X$ after traveling for a certain amount of time. How many miles of the rail tracks had train $A$ traveled when the two trains passed each other?

1. (1) Up to point $X$, the average speed of train $B$ was $25\%$ less than the average speed of train $B$.
2. (2) Up to point $X$, the average speed of train $B$ was $60$ mph and it took two and a half hours for train $B$ to arrive at point $X$.

1. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
2. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
3. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
4. EACH statement ALONE is sufficient.
5. Statements (1) and (2) TOGETHER are NOT sufficient.

 
Try the following GMAT Problem Solving question on functions and algebraic manipulation.

Question 44:

The function $f$ is defined by $f(x)=1-x^2$ for all values of $x$. What is $-f(-f(-x))$ ?

1. $\quad 0$

2. $\quad x^2-2x$

3. $\quad x^2+2x$

4. $\quad x^4-2x^2$

5. $\quad x^4+2x^2$