Question

157-150+143-136+...+17-10+3=?помогите пожалуйста​

Answer 1

157-150=7+143=150-136=14+17=31-10=21+3=24

ответ 24

Answer 2

Calculating the Sum of the Given Sequence

To find the sum of the given sequence 157-150+143-136+...+17-10+3, we can first simplify the sequence by combining the terms.

The given sequence can be simplified as follows: 157 - 150 = 7 143 - 136 = 7 ... 17 - 10 = 7 3

Now, we can see that the simplified sequence consists of a series of 7's with a single 3 at the end.

Calculating the Sum

To find the sum of this simplified sequence, we can use the formula for the sum of an arithmetic series:

Sum = (n/2)(first term + last term)

In this case, the first term is 7, the last term is 3, and the number of terms (n) can be calculated by adding 1 to the number of 7's in the sequence.

Calculating the Number of Terms

To find the number of terms in the sequence, we can calculate the difference between the first and last terms and then divide by the common difference.

The common difference in the simplified sequence is 7, and the first term is 7, while the last term is 3.

Number of terms = (last term - first term) / common difference + 1

Number of terms = (3 - 7) / (-7) + 1

Number of terms = -4 / -7 + 1

Number of terms = 4/7 + 1

Number of terms = 1 + 4/7

Number of terms = 11/7

Calculating the Sum

Now that we have the number of terms, we can use the formula for the sum of an arithmetic series to find the total sum.

Sum = (n/2)(first term + last term)

Sum = (11/2)(7 + 3)

Sum = (11/2)(10)

Sum = 55

So, the sum of the given sequence 157-150+143-136+...+17-10+3 is 55.