Pre-Algebra : Pre-Algebra

Study concepts, example questions & explanations for Pre-Algebra

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Example Questions

Example Question #1131 : Pre Algebra

Solve:

\displaystyle 15^{2}-12^{2}+7

Possible Answers:

\displaystyle 112

\displaystyle 81

\displaystyle 88

\displaystyle 75

Correct answer:

\displaystyle 88

Explanation:

To complete a problem with order of operations, follow the acronym PEMDAS to remember the order of completion. PEMDAS stands for:

Parentheses, Exponents, Multiplication and Division, Addition and Subtraction.

For this problem, we solve the exponents before completing addition and subtraction to get our final answer of 88:

\displaystyle 15^{2}-12^{2}+7

\displaystyle 225-12^{2}+7

\displaystyle 225-144+7

\displaystyle 81+7=88

Example Question #1132 : Pre Algebra

Solve:

\displaystyle 6\cdot2+(7-2\cdot 3+11)

Possible Answers:

\displaystyle 38

\displaystyle 12

\displaystyle 24

\displaystyle 34

Correct answer:

\displaystyle 24

Explanation:

To complete a problem with order of operations, follow the acronym PEMDAS to remember the order of completion. PEMDAS stands for:

Parentheses, Exponents, Multiplication and Division, Addition and Subtraction.

For this problem, we need to solve what is inside the parentheses first. In order to do this, solve the multiplication before the addition and subtraction. Complete the multiplication outside the parentheses, then solve the addition between that answer and the answer from the parentheses to get a final answer of 24:

\displaystyle 6\cdot2+(7-2\cdot 3+11)

\displaystyle 6\cdot2+(7-6+11)

\displaystyle 6\cdot2+(1+11)

\displaystyle 6\cdot2+12

\displaystyle 12+12=24

Example Question #1133 : Pre Algebra

Solve:

\displaystyle (12-3)\cdot (5+6)

Possible Answers:

\displaystyle 11

\displaystyle 20

\displaystyle 99

\displaystyle 2

Correct answer:

\displaystyle 99

Explanation:

To complete a problem with order of operations, follow the acronym PEMDAS to remember the order of completion. PEMDAS stands for:

Parentheses, Exponents, Multiplication and Division, Addition and Subtraction.

For this problem, we need to solve the inside of each set of parentheses first. Once we get these answers, multiply them together to get the final answer of 99:

\displaystyle (12-3)\cdot (5+6)

\displaystyle 9\cdot (5+6)

\displaystyle 9\cdot11=99

Example Question #1134 : Pre Algebra

Solve the following using the order of operations.

\displaystyle 8 \cdot 4 + 12 \div 6-(9-4)

Possible Answers:

\displaystyle 29

\displaystyle 25

\displaystyle 44

\displaystyle 39

\displaystyle 2

Correct answer:

\displaystyle 29

Explanation:

The order of operations is the order in which you must solve problems.  The order is

Parentheses

Exponents

Multiplication

Division

Addition

Subtraction

where you start with parentheses and follow the order until you reach subtraction. So we will follow the order for this problem

\displaystyle 8 \cdot 4 + 12 \div 6-(9-4)

Parentheses

\displaystyle 8 \cdot 4 + 12 \div 6-5

Multiplication

\displaystyle 32 + 12 \div 6-5

Division

\displaystyle 32 + 2-5

Addition

\displaystyle 34-5

Subtraction

\displaystyle 29

Example Question #1135 : Pre Algebra

Solve the equation below:

\displaystyle 8 + 4 * 6 - 12 =

Possible Answers:

\displaystyle 16

\displaystyle 0

\displaystyle 60

\displaystyle 6

\displaystyle 20

Correct answer:

\displaystyle 20

Explanation:

When solving an order of operations question use the GEMDAS method.

G = Grouping Symbols

E = Exponets

M/D = Multiplication OR Division from left to right.

A/S = Addition OR Subtraction from left to right.

\displaystyle 8 + 4 * 6 - 12 =

\displaystyle 4 * 6 = 24

\displaystyle 8 + 24 - 12 =

\displaystyle 32 - 12 = \displaystyle 20

Example Question #1136 : Pre Algebra

Solve using the order of operations:

\displaystyle 9 \cdot 3^2 + 12 \div 3

Possible Answers:

\displaystyle 85

\displaystyle 58

\displaystyle 22

\displaystyle 76

\displaystyle 31

Correct answer:

\displaystyle 85

Explanation:

The order of operations is the order in which you must solve a problem.  The order is defined as

PARENTHESES

EXPONENTS

MULTIPLICATION

DIVISION

ADDITION

SUBTRACTION

where we solve parentheses first, followed by exponents, and so on.  Following the order of operations, we get

\displaystyle 9 \cdot 3^2 + 12 \div 3

\displaystyle 9 \cdot 9 + 12 \div 3

\displaystyle 81 + 12 \div 3

\displaystyle 81 + 4

\displaystyle 85

Example Question #1137 : Pre Algebra

Solve using the order of operations:

\displaystyle 4(3^2 + 5^2) - 24 \div 2

Possible Answers:

\displaystyle 50

\displaystyle 56

\displaystyle 20

\displaystyle 124

\displaystyle 148

Correct answer:

\displaystyle 124

Explanation:

The order of operations is a specific order in which you must solve a problem.  It is defined as

PARENTHESES

EXPONENTS

MULTIPLICATION

DIVISION

ADDITION

SUBTRACTION

where you solve parentheses first, followed by exponents, and so on.  

So, following this order, we get

\displaystyle 4(3^2 + 5^2) - 24 \div 2

PARENTHESES

\displaystyle 4(9 + 25) - 24 \div 2

\displaystyle 4(34) - 24 \div 2

MULTIPLICATION

\displaystyle 136-24 \div 2

DIVISION

\displaystyle 136 - 12

SUBTRACTION

\displaystyle 124

Example Question #1138 : Pre Algebra

What is the solution to the following problem?

\displaystyle 2(4-3)^{2}+14 

Possible Answers:

\displaystyle 40

\displaystyle 21

\displaystyle 16

\displaystyle 28

\displaystyle 18

Correct answer:

\displaystyle 16

Explanation:

This problem requires proper order of operations. Remember the acronym for the order of operations: PEMDAS. This acronym will help you to remember the proper order for solving problems:

  1. Parentheses
  2. Exponents
  3. Multiplication and Division (whichever comes first as you read the problem from left to right)
  4. Addition and Subtraction (whichever comes first as you read the problem from left to right)

Step 1: Parentheses

\displaystyle 2(4-3)^{2}+14

\displaystyle 2(1)^{2}+14

Step 2: Exponents

\displaystyle 2(1)^{2}+14=2(1\cdot 1)+14=2(1)+14

Step 3: Multiplication

\displaystyle 2(1)+14=2+14

Step 4: Addition

\displaystyle 2+14=16

Example Question #122 : Operations And Properties

Fifty friends are renting a restaurant venue for a graduation party. Rental of the venue requires a \displaystyle \$315.00 up-front deposit plus a \displaystyle \$25.00 per hour operation cost. The friends have booked the venue from \displaystyle 8:00$ AM to \displaystyle 5:00 $ PM. If the friends have agreed to split the cost evenly, how much money should each person expect to pay? 

Possible Answers:

\displaystyle \$10.80

\displaystyle \$31.30

\displaystyle \$9.80

\displaystyle \$6.80

\displaystyle \$6.30

Correct answer:

\displaystyle \$10.80

Explanation:

First, let's write an equation that will calculate the cost for each person.

We need to calculate the number of hours that the students plan to rent the venue from \displaystyle 8:00$ AM to \displaystyle 5:00 $ PM.

Let's add these values together to calculate our x-variable (i.e. the number of hours that the students will rent the venue).

Now, we can substitute in the number of hours that the students will rent the venue and calculate the cost that each student should expect to pay.

Last, we need to divide this total cost by the number of students. 

Example Question #1139 : Pre Algebra

Fahrenheit temperature can be converted to its Celsius equivalent using the following formula:

.

Similarly, Celsius temperature can be converted to its Fahrenheit equivalent using another formula:

.

A scientist knows that nickel melts at the following temperature:

In order to complete an experiment, the scientist needs to know this temperature in degrees Fahrenheit. What is the melting point of nickel in degrees Fahrenheit?

Possible Answers:

\displaystyle 791^\circ $F

\displaystyle 776^\circ $F

None of these

Correct answer:

Explanation:

Since we are converting from Celsius to Fahrenheit, we need to use the following formula:

 .

Substitute the value for the melting point of nickel in degrees Celsius and solve. 

According to the order of operations, we need to perform the multiplication/division operations first.

Simplify.

Solve.

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