Respuesta :
Answer:
Correct answer: Â pt = 7,000 minutes
Step-by-step explanation:
This is arithmetic series:
pâ = 40 min
pâ = pâ + 20
pâ = pâ + 20 = pâ + 2 ¡ 20
pâ = pâ + 20 = pâ + 3 ¡ 20
...........................................
pâ = pâ + (n - 1) ¡ 20
25 - th day will be practicing:
pââ = 40 + 24 ¡ 20 = 520 minutes
The total sum of the arithmetic series is calculated according to the following formula:
Sâ = (n/2) (pâ + pâ)
In 25 days he will have practiced total minutes
pt = (25/2) ¡ ( 40 + 520) = (25/2) ¡ 560 = 7,000 minutes
pt = 7,000 minutes
God is with you!!!
Answer: he would have practiced for 7000 minutes in 25 days.
Step-by-step explanation:
His practice time is increasing in arithmetic progression each day. The formula for determining the sum of n terms of an arithmetic sequence is expressed as
Sn = n/2[2a + (n - 1)d]
Where
n represents the number of terms in the arithmetic sequence.
d represents the common difference of the terms in the arithmetic sequence.
a represents the first term of the arithmetic sequence.
From the information given,
a = 40 minutes
d = 20 minutes
For minutes practiced in 25 days,
n = 25
Therefore, the sum of the first 25 terms, S205 would be
S25 = 25/2[2 Ă 40 + (25 - 1)20]
S25 = 12.5[80 + 480)
S25 = 12.5 Ă 560 = 7000