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.
A 180 degree torn was made by the minute hand
Answer:
95
Step-by-step explanation:
5$ less 50 for the jacket half 50 +50 = 100 -5 =95
Question:
A cinema can hold 270 people at one performance 5/9 of the seats were occupied of the occupied seats 40% we occupied by concessionary ticket holders.
What is the number of seats occupied by concessionary ticket holders?.
Answer:
60 seats
Step-by-step explanation:
Given
Number of seats = 270
Occupied Seats = 5/9
Concessionary ticket holders = 40% of occupied Seats
Required
The number of seats occupied by concessionary ticket holders
First the number of occupied seat has to be calculated.



Next is to determine the number of seats occupied by concessionary ticket holders.


Convert percentage to decimal


<em>Hence, 60 seats were occupied by concessionary ticket holders.</em>
His error is the second choice.
Aiden should have calculated
area = (1.1 * 5.4) / 2
because triangle area = half the base times the altitude.