Answer:
Tr = 128(1/2)^r
Step-by-step explanation:
After round 1, half of 128 is eliminated = 128/2 = 64
After round 2, half of 64 is eliminated = 64/32 = 32
After round 3, half of 32 is eliminated = 32/2 = 16
After round four, half of 16 is eliminated which is 16/2 = 8
Now, the pattern we have is;
128, 64, 32, 16, 8
The succeeding term keeps decreasing by 2 compared to the preceding term
We can see that this is a geometric pattern with a = 128 and r = 1/2
The nth term is thus
Tn = 128 * (1/2)^n
Thus, the number of teams remaining after r round would be
Tr = 128 * (1/2)^r