Students

In the front row sitting three students and in every other row 11 students more than the previous row. Determine how many students are in the room when the room is 9 lines, and determine how many students are in the seventh row.

Correct result:

x =  423
a7 =  69

Solution:

a=3 d=11 n=9 b=a+(n−1)⋅ d=3+(9−1)⋅ 11=91 x=n⋅ (a+b)/2=9⋅ (3+91)/2=423
a7=a+(7−1)⋅ d=3+(7−1)⋅ 11=69

Try another example


We would be very happy if you find an error in the example, spelling mistakes, or inaccuracies, and please send it to us. We thank you!






Showing 0 comments:
avatar




You need to know the following knowledge to solve this word math problem:

Next similar math problems:

  • Apples in baskets
    basket Determine how many apples are in baskets when in the first basket are 4 apples, and in any other is 29 apples more than the previous, and we have eight baskets.
  • Seats
    divadlo_2 Seats in the sport hall are organized so that each subsequent row has five more seats. First has 10 seats. How many seats are: a) in the eighth row b) in the eighteenth row
  • Sequence 3
    75 Write the first 5 members of an arithmetic sequence: a4=-35, a11=-105.
  • Sequence
    sunflower Between numbers 1 and 53 insert n members of the arithmetic sequence that its sum is 702.
  • Sum of members
    seq_5 What is the sum of the first two members of the aritmetic progression if d = -4.3 and a3 = 7.5?
  • Trees
    tree_1 A certain species of tree grows an average of 0.5 cm per week. Write an equation for the sequence that represents the weekly height of this tree in centimeters if the measurements begin when the tree is 200 centimeters tall.
  • AS sequence
    AP In an arithmetic sequence is given the difference d = -3 and a71 = 455. a) Determine the value of a62 b) Determine the sum of 71 members.
  • Series
    fib Your task is express the sum of the following arithmetic series for n = 14: S(n) = 11 + 13 + 15 + 17 + ... + 2n+9 + 2n+11
  • Sequence
    a_sequence Write the first 7 members of an arithmetic sequence: a1=-3, d=6.
  • Nineteenth member
    seq_sum_1 Find the nineteenth member of the arithmetic sequence: a1=33 d=5 find a19
  • Consecutive numbers
    progression Sum of ten consecutive numbers is 105. Determine these numbers (write first and last).
  • AP - simple
    sigma_1 Determine the first nine elements of sequence if a10 = -1 and d = 4
  • Sequence
    seq_1 Write the first 6 members of these sequence: a1 = 5 a2 = 7 an+2 = an+1 +2 an
  • What is 9
    seq What is the 15th term; x1=1.5, d=4.5?
  • Sequence 2
    seq2 Write the first 5 members of an arithmetic sequence a11=-14, d=-1
  • 6 terms
    arithmet_seq Find the first six terms of the sequence. a1 = 7, an = an-1 + 6
  • Find the sum
    arithmet_seq_2 Find the sum of all natural numbers from 1 and 100, which are divisible by 2 or 5