# Mental Mat Quiz - non traditional algorithm

Mathematics is not about numbers, equations, computations, or algorithms: it is about understanding.

William Paul Thurston

Name _________________________________________

*Directions*: The idea is to work all problems in your head withour using a traditional algorithm. Write answers only. Take only ten minutes to complete it.

- 48 + 39 = _______
- 113 – 98 = _______
- 14 x 5 x 7 = _______
- 4 x 249 = _______
- 6(37 + 63) + 18 = _______
- .25 x 9 = _______
- 1/2 + 1/3 = _______
- 152 – 75 = _______
- 85/39 is closest to what integer? _______
- 12.03 + .4 + 2.36 = _______
- If you buy items priced (tax included) at $1.99, $2.99 and $3.98, your change from a $10 bill would be? _______
- 90% of 160 = _______
- To the nearest dollar, the sale price of a dress listed at $49.35 and sold at 25% off is _______.
- The sum of the first ten odd positive integers (1 + 3 + 5 + 7 + 9 … 17 + 19) is _______.
- The area of a square region of pe
- rimeter of 20 is _______.
- The ratio of the area of a circular region of radius one to that of the circumscribed square region is closest to .5, .6, .7 , .8, .9

(Circular region with area of one and circumscribed square region)

- The average (arithmetic mean) of 89, 94, 85, 90 and 97 is _______.
- If 4/6 = 16/x, then x = _______.
- If 2x + 3 = 25, then x = _______.
- √75 is closest to which integer? _______.
- To the nearest dollar, a 15% tip on a restaurant bill of $79.87 is _______.