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Lesson Example Discussion Quiz: Class Homework

Step-3

Title: Order of Operations

Grade: 6-a Lesson: S1-L7

Explanation: Hello Students, time to practice and review the steps for the problem.

Lesson Steps

Step	Type	Explanation	Answer
1	Problem	Simplify the expression: \$ 4^2 + 6 \div 2 times 3 − 5 \$
2	Step	The given expression	\$ 4^2 + 6 \div 2 times 3 − 5 \$
3	Hint	To simplify the expression, let’s follow the PEMDAS rule	Parentheses Exponents Multiplication and Division (from left to right) Addition and Subtraction (from left to right)
4	Step	First, calculate the exponent	\$ 4^2 = 16 \$ \$ 16 + 6 \div 2 times 3 − 5 \$
5	Step	Now, perform the division	\$ 6 \div 2 = 3 \$ \$ 16 + 3 times 3 − 5 \$
6	Step	Next, perform the multiplication	\$ 3 times 3 = 9\$ 16 + 9 − 5
7	Step	Finally, add and subtract from left to right:	16 + 9 = 25 25 − 5 = 20
8	Step	So, the value of the expression is 20.
9	Choice.A	This result is not correct because only one part of the expression was evaluated	10
10	Choice.B	Mismatched expression; could be due to incorrect addition of 16 from 4^2 to the result of 6 ÷ 2 × 3 − 5	12
11	Choice.C	Incorrect calculation due to incorrect order of operations	25
12	Choice.D	This matches the calculated result of the expression, so it’s the correct answer	20
13	Answer	Option	D
14	Sumup	Can you summarize what you’ve understood in the above steps?

Step

Type

Explanation

Answer

Problem

Simplify the expression:
\$ 4^2 + 6 \div 2 times 3 − 5 \$

Step

The given expression

\$ 4^2 + 6 \div 2 times 3 − 5 \$

Hint

To simplify the expression, let’s follow the PEMDAS rule

Parentheses
Exponents
Multiplication and Division (from left to right)
Addition and Subtraction (from left to right)

Step

First, calculate the exponent

\$ 4^2 = 16 \$

\$ 16 + 6 \div 2 times 3 − 5 \$

Step

Now, perform the division

\$ 6 \div 2 = 3 \$

\$ 16 + 3 times 3 − 5 \$

Step

Next, perform the multiplication

\$ 3 times 3 = 9\$

16 + 9 − 5

Step

Finally, add and subtract from left to right:

16 + 9 = 25

25 − 5 = 20

Step

So, the value of the expression is 20.

Choice.A

This result is not correct because only one part of the expression was evaluated

Choice.B

Mismatched expression; could be due to incorrect addition of 16 from 4^2 to the result of 6 ÷ 2 × 3 − 5

Choice.C

Incorrect calculation due to incorrect order of operations

Choice.D

This matches the calculated result of the expression, so it’s the correct answer

Answer

Option

Sumup

Can you summarize what you’ve understood in the above steps?