6. Leon says he can find the sum of 30 + 67 without

rewriting it. Explain how you can solve this problem

using mental math.

Why do scientists use the international system of units (SI)

Katie knew that 70 + 70 = 140. Explain how she can use this double to solve 70 + 80.

Solve using cross multiplication method, ax + by = a^2; bx + ay = b^2

Which of the following functions is quadratic? a. f (x) = 5/x-1 b. f (x) = 2^2 c. 7x (x+3) d. f (x) = 3 (4-x)

To borrow money, you pawn your guitar. Based on the value of the guitar, the pawnbroker loans you $960. One month later, you get the guitar back by paying the pawnbroker $1170. What annual interest rate did you pay?

Every sixth visitor to an animal gets a free animal calendar. every twentieth visitor gets a free animal toy. which visitor each day will be the first one to get both the calendar and the animal toy?

What is the measure of the angle between a perpendicular bisector and the segment it is bisecting? A. 180° B. 90° C. 45° D. 0°

How many sides does a regular polygon have that has an angle of rotation equal to 20 degrees.

A. How many lines of reflection symmetry does a hexagon have? B. How many degrees is one rotation that will put a hexagon back on top of itself.

There are 125 people in a sport centre. 59 people use the gym. 70 people use the swimming pool. 55 people use the track. 25 people use the gym and the pool. 30 people use the pool and the track. 17 people use the gym and the track.