How do three numbers add up to thirty?

It is impossible to solve the problem of how three numbers add up to thirty.

Because every number is odd, the addition of three can only be odd, not even.

Three numbers add up to 39+10+11= 30.

4.9.6.2.8.7 How do the three numbers add up and the other three numbers 4+9+6+2+8+7=36?

So you need to add three numbers = 18.

4+6+8=9+2+7

1, 3.5.7.9.11.13.15, how do three numbers add up to thirty? At first glance, this problem seems to have no solution, because all given are odd numbers, and the sum of three odd numbers must still be odd. So it can't be thirty. The following summarizes two kinds of problem-solving ideas summarized online for your reference only.

Reference 1: unit of use

For example, 1 day+1 hour +5 hours =30 hours.

Reference 2: Using Decimal System

But from another angle, what if the number given above is not a decimal? For example, in 1 1,15+1= 30. As long as it is an odd system, the three numbers 1 13 15 become even numbers, and there can be many such solutions.

1.3.5.7.9.1.13.15, how do the first three numbers add up to 30? There is no solution to this problem in middle school, which is determined by the nature of odd and even numbers.

Odd number (English: odd number) is also called odd number in spoken language. Among the integers, the number divisible by 2 is even, the number divisible by 2 is odd, and the odd number is 1, 3, 5, 7, 9. Even numbers can be represented by 2k, and odd numbers can be represented by 2k+ 1, where k is an integer.

Among natural numbers, numbers that are not divisible by 2 are called odd numbers. In daily life, people usually call odd numbers singular, as opposed to even numbers.

There must be an odd number and an even number in two consecutive integers.

The sum of odd numbers and odd numbers is even; The sum of even and odd numbers is odd; The sum of any number of even numbers is even. The sum of two numbers with the same parity is even; The sum of two numbers with different parity is odd.

The difference between two odd (even) numbers is even; The difference between even and odd numbers is odd numbers.

If a and b are integers, the parity of a+b and a-b is the same, that is, a+b and a-b are both odd or even.

The product of n odd numbers is odd, and the product of n even numbers is even; If one cis is even, the product is even, that is, A * B * C *……* ... * even *X*Y= even, where a, b, c, ... x, y are integers, and the formula can be simplified as: odd * even = even.

Odd numbers are 1, 3, 5, 7, 9; Even numbers are 0, 2, 4, 6 and 8.

Divide the square of an odd number by 2, 4 and 8, and the remainder is 1.

The square difference between any two odd numbers is a multiple of 2, 4 and 8.

Odd numbers are not divisible by 2; It was split in two and still one.

Because the numbers given in this question are all odd numbers, and the sum of three odd numbers is still odd, it is impossible to get an even number of 30, so this question has no solution.

However, in universities, there will be a solution to this problem, and the solution involves derivatives.

Derivative is an important basic concept in calculus. When the independent variable x of the function y=f(x) generates an increment δ x at the point x0, if δ x approaches 0, there is a limit a in the ratio of the increment δ y of the function output value to the increment δ x of the independent variable, then A is the derivative at x0, which is denoted as f'(x0) or df/dx(x0).

The derivative of any constant is 0 and the sign of the derivative is', so the three spaces are 15, 15, 15'. 15'=0, so15+15+15' = 30.

I hope it can help you solve the problem.

. 3.5.7.9.11.13.15 add up to three numbers that are 30 1. If it is decimal addition, three odd numbers can't add up to an even number. There is no solution to this problem.

2. If it is 1 1 decimal addition, the answer is 7+11+13 = 30.

3. If it's a brain teaser, the answer is 5.1+1.9+13 = 30.

The sum of1.3.5.7.9.1.13.15 cannot be even.

1.3.5.7.9.1.13.15 There is no solution to the problem that any three numbers add up to 30, because three odd numbers can't add up to an even number.

So we can only use a special method, empty 15+ 15+ 30.

The sum of1.3.5.7.9.1.13.15. is equal to 30, so we need to solve it. Option 1: 3! + 1 1+ 13=30 (3! =6)

Option 2: Log3 (9)+3? + 1=30 ( Log3 (9)=2，)

Scheme 3: 5.5+9.5+ 15=30.

Scheme 4:1'+15+15 = 30 (the derivative of any constant is 0).

Option 5: 3? +3+ 1'=30 (3? =27 1'=0)

Option 6: 3? +9-3! =30 (use negative numbers)

Scheme 7:11+13+(6) = 30 (reversing 9 to 6 is opportunistic).