Step-by-step explanation:
Initially, there's only 1 letter.
Tania sends the letter to 4 friends.
Each friend sends a letter to 4 more friends (4 × 4 = 16).
Each of those friends sends to 4 more friends (16 × 4 = 64).
The pattern is 1, 4, 16, 64, etc.
This is a geometric sequence. The first term is 1 and each term is 4 times the previous term.
a₁ = 1
aₙ = 4 aₙ₋₁
The explicit formula is:
aₙ = 1 (4)ⁿ⁻¹
Answer:
96
Step-by-step explanation:
First we need to know the mean of the Steve's scores on 6 of his tests. Given the six scores as 92, 78, 86, 92, 95, and 91.
Mean = sum of the scores/Total test taken
Mean = 92+78+86+92+95+ 91/6
Mean = 534/6
Mean = 89
If he took the seventh test and the mean score is raised by 1 them the new mean will be expressed as;
New mean = 92+78+86+92+95+ 91+x/7 = 89+1
Where x is the new score. Note that of a new score is added, the total year taken will also change to 7
To get x;
92+78+86+92+95+ 91+x/7 = 89+1
92+78+86+92+95+ 91+x/7 = 90
534+x/7 = 90
Cross multiply
533+x = 90×7
533+x = 630
x = 630-534
x = 96
Hence the score of the seventh test is 96
The answer is 169 ..... I hope this helps :)
Answer:
:)
Step-by-step explanation:
y=6x-3
y=-3
-3=6x-3
-3=6x-3
+3 +3
=6x