Order of Operations What does Please Excuse my

Order of Operations What does Please Excuse my Dear Aunt Sally REALLY Mean?

MOST COMMON MISTAKE • Most students and ADULTS! think that addition/subtraction means do all addition then do all subtraction. • THIS IS A BIG NO NO!!!!!! • Treat addition and subtraction like they are the same. This is called the left to right rule • 24 – 8 + 6 = 16 + 6 = 22 NOT

PEMDAS mistakes part 2 • Parenthesis: Do all of the operations within a parenthesis according to the order of operations • REMEMBER! If you have a fraction bar you must pretend that the numerator is enclosed as well as the denominator • Example

Your turn

Real Life Problem • You are playing basketball. You make 8 baskets and 2 free throws. Your friend makes half as many baskets as you and no free throws. How many points ahead of your friend are you? 8 × 2 + 2 × 1 – (8× 2)/2 = 16 + 2 – 16/2= 16+2 -8 = 18 – 8 10 points

Practice makes Perfect • Do problems 3 -16 on Page 18 even • Also do Page 19 #36 – 41 even HOW DID YOU DO? ? ? Calculate your percent correct? Over 60%: CRCT no problem Over 70%: I will pass Mrs. Rose’s class!!!!!!

More Practice • Page 19 and 20 #42 – 52 • Wrap it up by writing a math problem that has all operations in it (PEMDAS) THEN! • Solve it using correct operational order • Solve it incorrectly using bad order! The best example of incorrect order will appear on the chapter test!!!!