Yes, 21 is a number in the Fibonacci sequence. Numbers are usually found by adding up 2 numbers.
3 x 7
5+5+5+5+1 That is only 5 numbers being added. There can be no answer for six numbers for the following reasons: The numbers are all odd. Two odd numbers make an even number. Two even numbers make an even number. 21 is odd. Take 6 odd numbers and add them up in pairs. Each pair of odd numbers gives an even number so there are 3 even numbers. Even + Even + Even = Even. So sum of any six odd numbers is even but 21 is not even.
Rational and irrational numbers.
When the "factors" of a number are listed, the list is usually restricted to positive factors. Then there would be no answer to the question, because no group of positive numbers can add up to make zero.
take it in turn to say up to 3 numbers. whoever says the number 21 has to to a dare. Hope this helps
I am not sure if any two consecutive numbers can add up to an even number.
Lets just say you have an answer of 7.89, OK? By rounding that number up, you make it 8. When you round up numbers, you take your number and kinda 'pull' it up to the closest whole number.
Not necessarily. For example 15 and 16 are composite numbers. They add to 31, which is a prime number. Similarly, the composite numbers 20 and 21 add up to 41, which is a prime number.