Order of Operations Introduction — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. Which expression equals 24?
A) (2+4)*4
B) 2+4*4+2
C) 2*(4+4)+8
D) (2+4*4)+2
Parentheses make (2+4)=6, and 6*4=24, matching the target value precisely.
2. Which expression matches 'subtract 3 from 9, then multiply by 5'?
A) 9-3*5
B) (9-3)*5
C) 9-(3*5)
D) 9*(3-5)
Parentheses force subtraction before multiplication, making (9-3)*5 the right translation of the story.
3. Where should parens go in 10-2*3+1 to get 25?
A) 10-(2*3+1)
B) (10-2*3)+1
C) (10-2)*3+1
D) 10-2*(3+1)
(10-2)*3+1 gives 8*3+1=25, the only expression yielding the desired value of twenty-five.
4. Which models 'Buy 5 packs of 6 cards then give 4 to a friend'?
A) 5+6*4
B) (5+6)*4
C) 5*(6+4)
D) 5*6-4
Multiplication produces total cards, then subtraction removes the four given away to the friend.
Part B: Fill in the Blank
Write the correct answer on each line.
1. Compute 18-2*3+5 = 17 using PEMDAS rules.
Multiplication priority gives 6, and remaining left-to-right addition and subtraction finish the calculation.
2. (15-3)/4+2 = 5 when parentheses are honored.
Parentheses lift subtraction up, producing 12/4+2=5 through careful PEMDAS sequencing.
3. Place parens in 3+5*2-1 to get 15: (3+5)*2-1.
Parentheses around (3+5) make 8*2-1=15, the only arrangement yielding fifteen as the result.
4. 24/(2+1)*2 equals 16 following correct order.
Parentheses make 24/3=8, then multiplying by 2 yields 16 through proper left-to-right execution.
5. (7+3)*2-4 equals 16 when computed correctly.
Parentheses prioritize addition; multiplication and subtraction follow PEMDAS to produce the correct value.