andrew is thinking of a number
it is:
•between 1 and 150
•one more than a square number
•three less than a cube number
•it is not a prime number
what's his number?
you must show all your reasoning.

Answer :

mhanifa

Answer:

122

Step-by-step explanation:

Number is:

  • between 1 and 150
  • one more than a square number  = there are 12 square numbers, from 1²=1 to 12² = 144
  • three less than a cube number , there are 5 cubes, 1³ = 1 to 5³ = 125
  • it is not a prime number

Let's try the cubes because there are only 5 of them:

1³ = 1

  • it won't work as after subtracting 3 we get negative;

2³ = 8

  • subtract 3, we get 5 which is also 1 more than a square number of 4, however 5 is prime number so excluded;

3³ = 27

  • subtract 3, we get 24, it won't work as 23 is not a perfect square;

4³ = 64

  • subtract 3, we get 61, it won't work as 60 is not a perfect square, also 61 is a prime number;

5³ = 125

  • subtract 3, we get 122, which is 1 more than 11²= 121  and is not a prime number, so this is the required number;

The number is between 1 and 150.

one more than a fair number  = there are 12 square numbers, from 1²=1 to 12² = 144.

three less than a cube number, there are 5 cubes, 1³ = 1 to 5³ = 125

it is not a prime number.

What is the prime number?

A prime number is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number.

For example, 5 is prime because the only ways of writing it as a product, 1 × 5 or 5 × 1, involve 5 itself.

Let's try the cubes because there are only 5 of them

1³ = 1

It won't work as after subtracting 3 we get negative

2³ = 8

subtract 3, we get 5 which is also 1 more than a square number of 4, however, 5 is a prime number so excluded

3³ = 27

subtract 3, we get 24, it won't work as 23 is not a perfect square

4³ = 64

subtract 3, we get 61, it won't work as 60 is not a perfect square, also 61 is a prime number

5³ = 125

subtract 3, we get 122, which is 1 more than 11²= 121  and is not a prime number, so this is the required number.

To learn more about the square number visit:

https://brainly.com/question/21694652

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