TRIANGULAR NUMBERS By arranging
bowling pins in their proper order, a
triangle is created. The table below
shows the number of rows of bowling
pins and the total number of pins in the triangle. The formula:
n * (n+1) / 2
can be used to find t, the total number of items in n rows. How many bowling pins would there be if 10 rows of pins were set up?
Rows 1 2 3 4
Pins 1 3 6 10
check your formula for row 4 , (n=4)
number of pins = 4(5)/2 = 10
checks out with your chart
so if n=10
number of pins = 10(11)/2 = 55
Thanks Reiny!
To find the total number of bowling pins in 10 rows, we can use the formula given:
t = n * (n + 1) / 2
Here, t represents the total number of pins and n represents the number of rows.
Substituting the value of n as 10 into the formula, we get:
t = 10 * (10 + 1) / 2
Simplifying the expression inside the brackets, we have:
t = 10 * 11 / 2
Now, we can perform the multiplication:
t = 110 / 2
And finally, we can divide to get the total number of bowling pins:
t = 55
Therefore, there would be a total of 55 bowling pins if 10 rows of pins were set up.