# 4th Grade - Parentheses Mean Do It First

 Grade Level: 4th Skill: Algebra Topic: Parentheses Mean Do It First Goal: Use parentheses to indicate which operation to perform first when writing expressions containing more than two terms and different operations. Skill Description: Understand that in an expression that uses parentheses, you conduct the operation in the parentheses first to solve the problem. For example: 1 x 3 + (18 -7) Solve parentheses (18 – 7): 1 x 3 + 11 Multiply 1 x 3: 4 + 11 Then, add 4 + 11 = 15

## Building Blocks/Prerequisites

### Sample Problems

 (1) Solve the expression: (14 ÷ 2) + 7 x ( 3 x 3) – 1 (112) (2) Compare the expressions: 15 – (2 x 3) O (36 – 4) ÷ 8 (9 > 4) (3) Add the parentheses to make the expression equal to 18: 4 x 5 -14 ÷ 7 [4 x 5 –(14 ÷ 7) = 18] (4) Find the value of the expression: (3 x 7) – (16 ÷ 2) (13) (5) Solve the equation to make both sides equal: (10 + □ ) ÷ 3 = (6 x 4) ÷ 3 (14)

### Learning Tips

 (1) Math Vocabulary Variable- a letter or symbol that stands for any number Equation- A number sentence which states that two amounts are equal (2 x 3 = 6). Expression- A part of a number sentence that has numbers and operation signs, but does not have an equal sign (13 + 2) – 4 Operation- Add, subtract, multiply or divide (+, - , x, ÷) (2) Remind child to solve mathematical problems that are in parentheses first, and then complete operations from left to right. Otherwise, they may not receive an accurate answer. Write an expression and move the parentheses around to show the child how the answers are not the same when you switch around the parentheses. (3) Basic Skill practice for addition, subtraction, multiplication and division. Review comparing numbers (<, >, =) (4) Color code operations (red, blue, green, yellow) with color pencils when writing out the problem. This will help the child practice ordering the operations correctly. 1st operation: Red 2nd Operation: Blue 3rd Operation: Green 4th Operation: Yellow (if necessary) 120 – (5 x 12) + 10 (5) PEMDAS (Please Excuse My Dear Aunt Sally) PEMDAS (Parentheses Exponents* Multiplication Division Addition Subtraction) An Acronym for the order of operations to solve expressions and equations. Children are able to remember this in order to solve expressions and equations in the correct order (great test-taking strategy). *Exponents will be used in 5th grade.

### Extra Help Problems

 (1) Solve the expression: (15 x 5) – 15 + 14 (46) (2) Solve the expression: 15 + (13 + 3) – 8 (23) (3) Solve the expression: (61 – 58) x 42 – 12 (114) (4) Solve the expression: 19 + (36 ÷ 6) x 18 (450) (5) Solve the expression: (20 x 10) – (5 x 12) + 7 (133) (6) Which expression has the value of 36: (a) 5 + (4 x 17) – 13 (b) (5 + 4) x (17- 13) (b) (7) Which expression has the value of 629: (a)69 + (40 x 14) (b) (69 + 40) x 14 (a) (8) Which expression has the value of 2,557: (a) (58 + 51) x 49 (b) 58 + (51 x 49) (b) (9) Which expression has the value of 1,282: (a) (30 x 43) – 8 (b) 30 x (43 – 8) (a) (10) Which expression has the value of 85: (a) (47 + 78) – 40 (b) 47 + (78 – 40) (a) (11) Add the parentheses to make the expression equal to 126: 5 + 4 x 17 – 3 [(5 + 4) x (17 – 3)] (12) Add the parentheses to make the expression equal to 17: 3 x 9 – 4 + 2 [3 x( 9 – 4) + 2] (13) Add the parentheses to make the expression equal to 792: 11-2 x 11 x 8 [(11-2 ) x (11 x 8)] (14) Add the parentheses to make the expression equal to 1,430: 26 + 29 x 12 + 14 [(26 + 29) x (12 + 14)] (15) Solve the equation to make both sides equal: (4 x 7) – 5 = (9 x □ + 5) (2) (16) Solve the equation to make both sides equal: 45 + (2 x 2) = (□ x7 ) (7) (17) Solve the equation to make both sides equal: 8 x (3 x 25) = (4 x 2) x □ (75) (18) Solve the equation to make both sides equal: (11 x 2) – 7 x 2 = 22 – (8 + □) (6) (19) Solve the equation to make both sides equal: 14- (3 x 4) = (3 x 3) - □ (7) (20) Compare the expressions: (23 +77) x 9 O (48 x 9) + 12 (900 > 444) (21) Compare the expressions: (59 x 30) + 5 O (5 x 59) – 30 (1,775 > 265) (22) Compare the expressions: 9 x 3 – (42 ÷ 7) O 9 ÷ 3 + (42 ÷ 7) (21 >9) (23) Compare the expressions: 23 x (77 + 9) O (88 – 64) x 42 (1,978 > 1,008) (24) Place the operations in the expression (+, -, ÷, x): 7 □ 12 □ 5 = 89 (7 x 12 + 5 = 89) (25) Place the operations in the expression (+, -, ÷, x): 9 4 11 = 48 (72 – 9) - (4 + 11)