Answer:
700 lei
Step-by-step explanation:
You have a geometric sequence for which you know the common ratio and the last term.
There are only three terms, so you can solve the problem in either of two ways.
1. The brute force method
(easiest for only a few terms)
Each term is half the one before it, so each term is double the one after it.
3rd term = 100 lei
2nd term = 200
1st term = 400
Total = 700 lei
Oana spent 700 lei
2. Using formulas (best for longer sequences)
The general formula for your sequence is
aₙ = a₁rⁿ⁻¹
For your sequence,
a₃ = 100; r = 0.5
(a) Calculate a₁
Set the last term equal to the general formula.
a₃ = a₁(0.5)ⁿ⁻¹
100 = a₁(0.5)² = 0.25a₁
a₁ = 100/0.25 = 400
(b) Calculate the sum
The general formula for the sum of a geometric sequence is
Oana spent 700 lei.
Answer:
Wag po kayo mag bibigay ng maraming points
maiiskam po kayo katulad neto
Answer:
cahrge 15 for first hours and 6 for every additional hour
Step-by-step explanation:
you get more money because if you do one hour then you will still get $15 in a hour while if you do one hour in the other equation yolu will only get $5
Are these three different questions? if so:
1: add 19 to both sides to get a = 3 +19
answer: a = 22
2: multiply both sides by 7 to get y = 10 * 7
answer: y = 70
3: divide both sides by 5 to get g = 100/5
answer: g = 20
hope this helped! good luck :)
Answer:
true
Step-by-step explanation: