Answer:
Option A - Permutation; number of ways = 210
Step-by-step explanation:
Given : At a competition with 7 runners, medals are awarded for first, second, and third places. Each of the 3 medals is different.
To find : How many ways are there to award the medals?
Solution :
There are 7 runners but medals are three.
The first runner up got first medal as one is locked.
The second runner up got second medal as second is locked.
The third runner up got the third medal.
So, There is a permutation.
Number of ways to award the medals is 
We know, 
Substitute the values,
Therefore, Option A is correct.
Permutation; number of ways = 210
............................................................60 and 78
4a. 99m + 81 = 130m. 4b. 40 + 30z = 70z
5a. 24v + 18 = 41v. 5b. 12c + 16 = 28c
6c. 44 + 48v= 92v. 6b. 40 + 12s = 52s.
Answer:
1.095, 1.152, 1.153, 1.338, 1.45, 1.729, 1.755, 1.806, 1.935, 1.993
Step-by-step explanation:
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
