All ISEE Lower Level Math Resources
Example Questions
Example Question #91 : Equations
If and , what is ?
Sometimes we use letters instead of numbers if we don't know what number ought to go in a certain place. Saying "" means that something plus eight equals fifteen, but we aren't yet certain what that "something" is. When we can, we solve the puzzle of what number that letter could be replaced with.
. , so must be replaced by .
. , so must be replaced by also.
We're looking for . To find this, we replace the letters with the numbers we found. and both equal , so .
, so . The correct answer is .
Example Question #91 : Equations
Solve the following equations:
To solve the equation you must get by itself. The first step is to add to both sides to offset the resulting in . The final step to get byitself is to divide both sides by which gives us .
Example Question #91 : Equations
Solve the following equation for c when .
Solve the following equation for c when .
We can begin by plugging in 6 for b:
Simplify
Next, take the square root of both sides to get:
Note that our answer is plus or minus five, because squaring positive or negative five will yield 25.
Example Question #94 : Equations
Solve the following equation for z when x=5, and y=2.
Solve the following equation for z when x=5, and y=2.
Let's begin by dividing the whole equation by 3. This will get "z" by itself and make our equaiton easier to work with.
Next, plug our given values in and simplify
So, we get:
Example Question #95 : Equations
If Timmy had pieces of gum yesterday, and only today, how many pieces did Timmy lose overnight?
To solve a word problem with an unknown quantity, treat the unknown quantity as a variable. The best equation for the problem above is:
Use algebra to solve.
Example Question #96 : Equations
An unknown number of children are on the bus on their way home from school. At the first stop, eight children get off the bus, at the second, fifteen get off, and at the third and final stop four children get off. There are no children left on the bus. How many were on the bus at the start of its route?
To solve a word problem with an unknown quantity, treat the unknown quantity as a variable. The best equation for the problem above is:
Example Question #91 : Equations
Mrs. Franklin has twenty stickers, and she wants to distribute them evenly among four students. How many stickers will each student receive?
To solve a word problem with an unknown quantity, treat the unknown quantity as a variable. The best equation for the problem above is:
Example Question #92 : Equations
If it costs twelve dollars to buy an action figure, and Joanna bought eight action figures, how much money did she pay for them?
To solve a word problem with an unknown quantity, treat the unknown quantity as a variable. The best equation for the problem above is:
Example Question #99 : Equations
Solve the following equation if .
Since you already know that is , you just plug it in for the variable in the equation.
This gives you,
.
Performing algebraic operations to simplify results in the following.
and
Therefore,
.
Example Question #94 : Equations
If the side of a square is , and the square’s area is 144 feet, what is the value of ?
The formula for the area of a square is length times width.
where thus the area formula becomes .
The question gives,
and
In order to solve this, substitute in the given information into the area formula.
From here find the square root of both sides.