Logs are stacked 7 rows high. The top row has 15 logs, the second row has 18 logs, and the third row has 21 logs. This pattern continues similarly.
What is the total number of logs in the stack?
15 + 18 + 21 + 24 + 27 + 30 + 33 = ?
we just want the answer
To find the total number of logs in the stack, we need to calculate the sum of logs in each row and then sum up the total number of logs in all the rows.
Let's calculate the number of logs in each row:
1st row: 15 logs
2nd row: 18 logs
3rd row: 21 logs
We can observe that each row has 3 logs more than the previous row. This pattern continues for all rows.
So, the 4th row will have 21 + 3 = 24 logs.
The 5th row will have 24 + 3 = 27 logs.
And so on...
Since the pattern continues until the 7th row, we need to calculate the number of logs for each row starting from the 3rd row (since we already know the number of logs in the 1st and 2nd row).
3rd row: 21 logs
4th row: 24 logs
5th row: 27 logs
6th row: 30 logs
7th row: 33 logs
Now, let's calculate the total number of logs in each row:
1st row: 15 logs
2nd row: 18 logs
3rd row: 21 logs
4th row: 24 logs
5th row: 27 logs
6th row: 30 logs
7th row: 33 logs
To find the total number of logs in the stack, we sum up all the logs in each row:
15 + 18 + 21 + 24 + 27 + 30 + 33 = 168
Therefore, the total number of logs in the stack is 168.
To find the total number of logs in the stack, we need to determine the number of logs in each row and then add them up to find the total.
From the given information, we know that the first row has 15 logs, the second row has 18 logs, and the third row has 21 logs.
To find the number of logs in subsequent rows, we can see that each row has 3 more logs than the row above it. This means that the fourth row will have 21 + 3 = 24 logs, the fifth row will have 24 + 3 = 27 logs, and so on.
So, the pattern continues like this:
1st row: 15 logs
2nd row: 18 logs
3rd row: 21 logs
4th row: 24 logs
5th row: 27 logs
Since the pattern continues in this way, we can determine the number of logs in each row by adding 3 to the number of logs in the previous row.
Now, let's calculate the number of logs in each row:
1st row: 15 logs
2nd row: 18 logs (15 + 3)
3rd row: 21 logs (18 + 3)
4th row: 24 logs (21 + 3)
5th row: 27 logs (24 + 3)
To find the total number of logs in the stack, we need to sum up the number of logs in each row.
Total = 15 + 18 + 21 + 24 + 27 + ...
Here, we can observe that each row increases by 3 logs, so we can represent the number of logs in each row as an arithmetic sequence with a common difference of 3.
Using the formula for the sum of an arithmetic sequence, which is given by S = (n/2)(a + l), where S is the sum of the sequence, n is the number of terms, a is the first term, and l is the last term, we can calculate the total number of logs.
In this case, the first term (a) is 15, and the common difference is 3.
Using the formula, we can find the number of terms by finding the row number (n). We are given that the logs are stacked 7 rows high.
Using the formula, we have:
Total = (n/2)(a + l)
Total = (7/2)(15 + l)
Since we don't have the specific number of logs in the 7th row, we can use the equation for the number of logs in a row, which is given by Ln = L1 + (n - 1)d, where Ln is the number of logs in the nth row, L1 is the number of logs in the first row, and d is the common difference.
So, for the 7th row, we have:
L7 = 15 + (7 - 1)3
L7 = 15 + 6 * 3
L7 = 15 + 18
L7 = 33
Substituting the known values into the formula for the total number of logs:
Total = (7/2)(15 + 33)
Total = (7/2)(48)
Total = 7 * 24
Total = 168
Therefore, the total number of logs in the stack is 168.