PEMDAS rule can be used to simplify complicated numerical expressions with more than operations.
Very simply way to remember PEMDAS rule!
P ----> Parentheses
E ----> Exponent
M ----> Multiply
D ----> Divide
A ----> Add
S ----> Subtract
1. In a particular simplification, if you have both multiplication and division, do the operations one by one in the order from left to right.
2. Multiplication does not always come before division. We have to do one by one in the order from left to right.
3. In a particular simplification, if you have both addition and subtraction, do the operations one by one in the order from left to right.
Evaluate each of the following numerical expressions.
Problem 1 :
[3 x (4 + 2)] x 5
Solution :
= [3 x (4 + 2)] x 5
= [3 x 6] x 5
= 18 x 5
= 90
Problem 2 :
[4 x (16 – 1)] – 6
Solution :
[4 x (16 – 1)] – 6
= [4 x 15] – 6
= 60 - 6
= 54
Problem 3 :
5 + [6 + (7 x 2)] ÷ 5
Solution :
= 5 + [6 + (7 × 2)] ÷ 5
= 5 + [6 + 14] ÷ 5
= 5 + 20 ÷ 5
= 5 + 4
= 9
Problem 4 :
3 – (-2 + 7) + 4
Solution :
= 3 – (-2 + 7) + 4
= 3 – 5 + 4
= -2 + 4
= 2
Problem 5 :
(18 ÷ 3) x (-2)
Solution :
= (18 ÷ 3) x (-2)
= 6 x (-2)
= -12
Problem 6 :
2(7 – 13) – (6 - 12)
Solution :
= 2(7 – 13) – (6 - 12)
= 2(-6) – (-6)
= -12 + 6
= -6
Problem 7 :
-6 x (2 – 7)
Solution :
= -6 x (2 – 7)
= -6 x (-5)
= 30
Problem 8 :
–(14 – 8) ÷ (-2)
Solution :
= –(14 – 8) ÷ (-2)
= -6 ÷ (-2)
= 3
Problem 9 :
-18 – (8 – 15)
Solution :
= -18 – (8 – 15)
=-18 – (-7)
= -18 + 7
= -11
So, the answer is -11.
Problem 10 :
-52 ÷ (6 – 19)
Solution :
= -52 ÷ (6 – 19)
= -52 ÷ (-13)
= 4
Problem 11 :
[38 - (-4)]/[6 x (-7)]
Solution :
= [38 - (-4)]/[6 x (-7)]
= [38 + 4]/[-42]
= 42/[-42]
= -1
Problem 12 :
[38 - (-4)]/[6 x (-7)]
Solution :
= [28 - (-3 x 4)]/[10 x (-2)]
= [28 - (-12)]/[-20]
= [28 + 12]/[-20]
= 40/[-20]
= -2
Problem 13 :
42 ÷ (15 − 23)
Solution :
= 42 ÷ (15 − 23)
= 42 ÷ (15 − 8)
= 42 ÷ 7
= 6
Problem 14 :
You need to read 20 poems in 5 days for an English project. Each poem is 2 pages long. Evaluate the expression 20 × 2 ÷ 5 to find how many pages you need to read each day.
Solution :
Evaluating the expression,
= 20 × 2 ÷ 5
From left to right for both multiplciation and division, we will give same importance.
= 40 ÷ 5
= 8
So, number of pages read each day is 8.
Your friend evaluates the expression. Is your friend correct? Explain your reasoning.
Problem 15 :
= 9 + 3 × 32
= 12 × 9
= 108
Solution :
The above calculation is incorrect, correct steps are
= 9 + 3 × 32
Use the exponents first,
= 9 + 3 × 9
Perform the multiplication.
= 9 + 27
Add these two terms,
= 36
The answer should be 36.
Problem 16 :
= 19 − 6 + 12
= 19 − 18
= 1
Solution :
The above calculation is incorrect, correct steps are
= 19 − 6 + 12
Adding the numbers,
= 31 - 6
= 25
So, the answer is 25.
Problem 17 :
The diagram shows landing zones for skydivers. Zone 1 is for experts. The remaining space is divided in half and designated as Zones 2 and 3 for tandem divers. What is the area of Zone 2?
Solution :
Area of zone 2
= (1/2) (area of square whose side length is 40 yards - area of square whose side length is 20 yards)
= (1/2) (402 - 202)
= (1/2)(1600 - 400)
= (1/2)(1200)
= 600 square yards.
Problem 18 :
A square vegetable garden has side lengths of 12 feet. You plant flowers in the center portion as shown. You divide the remaining space into 4 equal sections and plant tomatoes, onions, zucchini, and peppers. What is the area of the onion section?
Solution :
Area of onion section
= (1/4) (area of square whose side length is 12 ft - area of square whose side is 4 ft)
= (1/4)(122 - 42)
= (1/4)(144 - 16)
= (1/4)(128)
= 32 square ft.
So, the required area is 32 square ft.
Kindly mail your feedback to v4formath@gmail.com
We always appreciate your feedback.
©All rights reserved. onlinemath4all.com
Jun 08, 25 09:22 AM
Jun 07, 25 09:17 PM
Jun 06, 25 07:10 PM