Answer: Aₙ = Aₙ₋₁*3; where A₀ = 2.5
Step-by-step explanation:
Let's try with some known sequences:
Arithmetic.
The difference between consecutive terms is constant:
7.5 - 2.5 = 5
22.5 - 7.5 = 15
We can already see that it is not an arithmetic sequence.
Geometric:
The ratio between consecutive terms is constant.
7.5/2.5 = 3
22.5/7.5 = 3
67.5/22.5 = 3
...
We can already see that this is a geometric sequence.
Then we can write the n-th term as:
Aₙ = Aₙ₋₁*3, where A₀ = 2.5
Answer:
We need to add:
5 + 5 + 2 = 12 friends voted for Dog
The correct answer is D)
In this question there are numerous information's that are given for getting the required answer. The most important of those informations is that the crew of workers required 20 minutes to pave 2/15 miles of the highway. It is required to find the portion of mile these workers will pave in 1 hour. We already know that 1 hour is equal to 60 minutes. This information will help to solve the problem.
In 20 minutes the crew of workers pave = 2/15 miles
In 60 minutes the crew of same workers will pave = (2/15) * (60/20)
= (2/15) * 3
= 2/5 miles
So the crew of workers working at the same rate will pave a portion of 2/5 miles in 1 hour.
Answer:
Natasha can wrap 128 gifts in total
Step-by-step explanation:
Let us use the ratio method to solve the question
∵ Natasha has 240 square feet of wrapping paper
∵ Natasha can wrap 8 gifts with 15 square feet
→ By using the ratio method
→ Gift : square feet
→ 8 : 15
→ x : 240
→ By using cross multiplication
∵ x × 15 = 8 × 240
∴ 15x = 1920
→ Divide both sides by 15
∵ x = 128
∵ x represents the number of gifts
∴ Natasha can wrap 128 gifts in total