All GMAT Math Resources
Example Questions
Example Question #1 : Calculating The Perimeter Of A Right Triangle
What is the perimeter of a traingle?
A triangle is a right triangle. To find the perimeter, we must add up all the sides of the triangle.
Example Question #21 : Right Triangles
A right triangle has a hypotenuse of length 13 yards and a leg of length 5 yards. Give the perimeter of this triangle in inches.
We can use the Pythagorean Theorem to calculate the length of the second leg in yards of the triangle by setting in this formula:
The perimeter of the triangle is yards is
yards. Multiply this by 36 to covert to inches:
inches.
Example Question #3 : Calculating The Perimeter Of A Right Triangle
A right triangle has legs of length feet and and feet. Give the perimeter of this triangle in yards.
We can use the Pythagorean Theorem to calculate the hypotenuse of the triangle by setting in this formula:
The perimeter is feet.
Divide by 3 to convert to yards:
yards
Example Question #2 : Calculating The Perimeter Of A Right Triangle
What is the perimeter of a 30-60-90 triangle?
1) One of the sides measures 10 inches.
2) One of the sides measures 20 inches.
EACH statement ALONE is sufficient.
BOTH statements TOGETHER are sufficient, but neither statement ALONE is sufficient.
Statement 2 ALONE is sufficient, but Statement 1 alone is not sufficient.
Statements 1 and 2 TOGETHER are not sufficient.
Statement 1 ALONE is sufficient, but Statement 2 alone is not sufficient.
BOTH statements TOGETHER are sufficient, but neither statement ALONE is sufficient.
The hypotenuse of a 30-60-90 triangle measures twice its shorter leg; its longer leg measures times its shorter leg. Given one side length alone, there is no indication which of the three sides it measures; but given two, one of which is twice the other, as is the case here (10 and 20), 10 must be the shorter leg and 20 the hypotenuse. The longer leg is therefore , and the perimeter is
.
Therefore, both statements together are sufficent but neither alone is sufficient.
Example Question #24 : Triangles
A right triangle has a base of 4 and a height of 3. What is the perimeter of the triangle?
We are given two sides of the right triangle, so in order to calculate the perimeter we must first find the length of the third side, the hypotenuse, using the Pythagorean theorem:
Now that we know the length of the third side, we can add the lengths of the three sides to calculate the perimeter of the right triangle:
Example Question #25 : Right Triangles
is a right triangle and and . What is half the circle's circumference added to the triangle's perimeter?
As you see that a right triangle as sides 3 and 4, you should always remember that, this right triangle is a Pythagorean Triple, in other words, its sides will be in the ratio where is a constant, this will save you a lot of time. Here we can say that the hypotenuse will be 5. Therefore, the circumference will be . To get the final answer, we should just divide the circumference by 2 and add the perimeter, being or 12.
Example Question #1 : Calculating The Area Of A Right Triangle
In the above figure, triangle SPQ, SPR and PRQ are right triangles. Given the lengths of SP and PQ are 2cm. What is the area of triangle SPR?
Since are right triangles, we know that is an isosceles right triangle. So we know that the lengths of and are 2 cm, so we can get the length of by using the Pythagorean Theorem:
is the midpoint of , so the length of is .
Now we can use the Pythagorean Theorem again to solve for : .
Finally, we have all the elements needed to solve for the area of :
Example Question #1 : Calculating The Area Of A Right Triangle
If a right triangle has a hypotenuse that is 10, and one side is 6, find the area of the triangle.
Becaue this is a right triangle and since the hypotenuse is 10 and one side is 6, the other side will be 8. This can be found using the Pythagorean Theorem, or multiplying a 3-4-5 triangle by 2 to get a 6-8-10 triangle. Since the area of a right triangle is half of the product of the two sides, we have
Example Question #28 : Right Triangles
The hypotenuse of a triangle is equal to the sidelength of a square. Give the ratio of the area of the square to that of the triangle.
Let be the sidelength of the square. Then its area is .
If the hypotenuse of a triangle is , its shorter leg is half that, or ; its longer leg is times the shorter leg, or . The area of the triangle is half the product of the legs, or
The ratio of the area of the square to that of the triangle is
or
or
Example Question #2 : Calculating The Area Of A Right Triangle
A triangle on the coordinate plane has vertices.
Which of the following expressions is equal to the area of the triangle?
This is a right triangle with legs along the - and -axes, so the area of each can be calculated by taking one-half the product of the two legs.
The vertical leg has length ; the horizontal leg has length .
Now calculate the area: