Estimate Shmestimate
Which benchmarks would you use to estimate the root of 95?
9 and 10
What is a prime number?
A whole number that only has two factors.
Which numbers are neither composite nor prime?
0 and 1
What is the square of 14?
196
Square root of 121?
11
Which benchmarks would you use to estimate the root of 150?
12 and 13
Give three examples of two-digit prime numbers.
(Responses vary)
Give three examples of 2-digit composite numbers.
Answers vary
What is the area of a square with side lengths 9cm?
81cm2
Square root of 225?
15
Estimate the root of 132 to the nearest tenth.
11.4 or 11.5
Express 32 as the product of prime numbers.
2x2x2x2x2 or 25
What is the smallest ODD composite number?
9
What are the side lengths of a square with an area of 56cm2 ? Round to the nearest tenth of a cm.
7.4 or 7.5
Square root of 90,000?
Estimate the root of 84 to the nearest tenth.
9.1 or 9.2
Find the prime factorization of 28.
2x2x7 or 22 x 7
What is the product of the first five composite numbers?
(4x6x8x9x10) = 17,280
Explain why 35 is a perfect square (or not) by listing its factors.
{1, 5, 7, 35} - Even number of factors.
Square root of 49,000,000?
7000
Estimate the square root of 410.
20.2 or 20.3
Explain how you can tell if a number is a perfect square when looking at its prime factorization.
If you can group its prime factors into two groups of the same prime factors, then it is a perfect square (Ie. (2x3) x (2x3) = 36)
Who discovered prime and composite numbers?
Explain why 64 is a perfect square (or not) by listing its factors.
{1,2,4,8,16,32,64} - Odd number of factors means middle one is square root!
Square root of 270,400?
520