Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

Find the value of the following expression and round to the nearest integer:

sum_(n=1)^(20)600(0.91)^(n+1)
Answer:

Find the value of the following expression and round to the nearest integer:\newlinen=120600(0.91)n+1 \sum_{n=1}^{20} 600(0.91)^{n+1} \newlineAnswer:

Full solution

Q. Find the value of the following expression and round to the nearest integer:\newlinen=120600(0.91)n+1 \sum_{n=1}^{20} 600(0.91)^{n+1} \newlineAnswer:
  1. Recognize Problem Type: Recognize that the given expression is a geometric series where the first term a1a_1 is 600(0.91)2600(0.91)^2, the common ratio rr is 0.910.91, and the number of terms nn is 2020.
  2. Use Geometric Series Formula: Use the formula for the sum of a finite geometric series, which is Sn=a1(1rn)/(1r)S_n = a_1(1 - r^n) / (1 - r), where SnS_n is the sum of the first nn terms.
  3. Calculate First Term: Calculate the first term a1a_1 by substituting n=1n=1 into the expression, which gives us a1=600(0.91)2a_1 = 600(0.91)^2.\newlinea1=600×(0.91)2a_1 = 600 \times (0.91)^2\newlinea1=600×0.8281a_1 = 600 \times 0.8281\newlinea1=496.86a_1 = 496.86
  4. Calculate Sum S20S_{20}: Calculate the sum S20S_{20} using the formula from Step 22 with a1=496.86a_1 = 496.86, r=0.91r = 0.91, and n=20n = 20.\newlineS20=496.86×(1(0.91)20)/(10.91)S_{20} = 496.86 \times (1 - (0.91)^{20}) / (1 - 0.91)
  5. Calculate (0.91)20(0.91)^{20}: Calculate (0.91)20(0.91)^{20} to find the value that will be subtracted from 11 in the numerator of the sum formula.\newline(0.91)200.151356(0.91)^{20} \approx 0.151356
  6. Substitute Value: Substitute the value from Step 55 into the sum formula to calculate S20S_{20}. \newlineS20=496.86×(10.151356)/(10.91)S_{20} = 496.86 \times (1 - 0.151356) / (1 - 0.91)\newlineS20=496.86×(0.848644)/0.09S_{20} = 496.86 \times (0.848644) / 0.09
  7. Perform Calculations: Perform the calculations to find the sum S20S_{20}. \newlineS20=496.86×0.848644/0.09S_{20} = 496.86 \times 0.848644 / 0.09\newlineS20=421.788/0.09S_{20} = 421.788 / 0.09\newlineS20=4686.53333333S_{20} = 4686.53333333
  8. Round to Nearest Integer: Round the sum S20S_{20} to the nearest integer.\newlineS204687S_{20} \approx 4687

More problems from Sum of finite series starts from 1