Problems session 1/23

Links and useful resources

• gr7's Prealgebra Course Outline START HERE<<<
• AoPS Online Textbook
• IXL Grade 7 index
• IXL Grade 8 index
• AoPS Alcumus
• IXL prealgebra practice index
• OpenSTAX Prealgebra-1 textbook

Serious considerations

• Why was the math book sad? It had a lot of problems.
• What do you call a boiling tea kettle on top of Mt. Everest? A high pot in use! (hypotenuse)
• What do you get when you drink root beer in a square glass? Beer!
• I’ll do algebra, I’ll even do trig, but graphing is where I draw the line!

Concept summary and lesson

• least common multiple
• greatest common divisor
• divisibility tests

Worked examples

Media resources

• Youtube search for "least common multiple"
• Youtube search for "greatest common divisor"
• Youtube search for "divisibility tests"

Guided practice

• One owl hoots every 3 hours, a second owl hoots every 8 hours, and a third owl hoots every 12 hours. If they all hoot together at the start, how many times during the next 80 hours will just two of the owls hoot together?
• When the six-digit number $3456n7$ is divided by 8, the remainder is 5. What are the two possible values of n?
• Find the largest factor of 2520 that is not divisible by 6.
• Simplify $\frac{x+2}{13}-\frac{2x-4}{39}$

Homework

• #hw (math) (gr7) 6.3 Decimals and Fractions (p. 263)