Geometric progressiob

If the sum of four consective terms of geometric progression is 80 and arithmetic mean of second and fourth term is 30 then find terms?

Correct result:

a =  2
b =  6
c =  18
d =  54


a+b+c+d=80 (b+d)/2=30 b=qa c=qb d=qc  a+c+2 30=80 a+c=20  a+aq2=20  a(1+q2)=20 qa(1+q2)=60 q=60/20=3  a=201+q2=201+32=2
b=q a=3 2=6
c=q b=3 6=18
d=q c=3 18=54

We would be pleased if you find an error in the word problem or inaccuracies and send it to us. Thank you!

Showing 0 comments:

Tips to related online calculators
Looking for help with calculating roots of a quadratic equation?
Do you have a linear equation or system of equations and looking for its solution? Or do you have quadratic equation?

Related math problems and questions:

  • Gp - 80
    gp_1 Sum of the first four members of a geometric progression is 80. Determine they if we know that the fourth member is nine times greater than the second.
  • Sequences AP + GP
    seq_sum The three numbers that make up the arithmetic sequence have the sum of 30. If we subtract from the first 5, from the second 4 and keep the third, we get the geometric sequence. Find AP and GP members.
  • Arithmetic progression 2
    seq_sum The 3rd term of an Arithmetic progression is 10 more than the first term while the fifth term is 15 more than the second term. Find the sum of the 8th and 15th terms of the Arithmetic progression if the 7th term is 7 times the first term.
  • What is 10
    numbers2_4 What is the 5th term, if the 8th term is 80 and common ratio r =1/2?
  • Three members GP
    exp_growth The sum of three numbers in GP (geometric progression) is 21 and the sum of their squares is 189. Find the numbers.
  • Sum of GP members
    exponentialFexsDecay Determine the sum of the GP 30, 6, 1.2, to 5 terms. What is the sum of all terms (to infinity)?
  • GP - three members
    progression_ao The second and third of a geometric progression are 24 and 12(c+1) respectively, given that the sum of the first three terms of progression is 76 determine value of c
  • Common difference
    apollo The 4th term of an arithmetic progression is 6. If the sum of the 8th and 9th term is -72, find the common difference.
  • If the 3
    sequence_geo If the 6th term of a GP is 4 and the 10th is 4/81, find common ratio r.
  • Geometric seq
    eq222_1 Find the third member of geometric progression if a1 + a2 = 36 and a1 + a3 = 90. Calculate its quotient.
  • Cube
    cube_diagonals_3 The sum of all cube edges is 30cm. Find the surface area of the cube.
  • Find the
    eq222_2 Find the number x, which if it increases by 2, then its square increases by 21 percent.
  • Geometric progression
    exp_1 In geometric progression, a1 = 7, q = 5. Find the condition for n to sum first n members is: sn≤217.
  • Terms of GP
    exp_growth What is the 6th term of the GP 9, 81, 729,. .. ?
  • The sum
    eq222_1 The sum of the squares of two immediately following natural numbers is 1201. Find these numbers.
  • Harmonic mean
    means_math If x, y, z form a harmonic progression, then y is the harmonic mean of x and z. Find the harmonic mean of the numbers 6 and 5.
  • Fifth member
    arithmet_seq_1 Determine the fifth member of the arithmetic progression, if the sum of the second and fifth members equal to 73, and difference d = 7.