SOLUTION: Is it B? I want to check my answer.
James decided to start exercising. The first day he jogged for 10 mins. The next day he wanted to jog for 4 more minutes than the previous da
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-> SOLUTION: Is it B? I want to check my answer.
James decided to start exercising. The first day he jogged for 10 mins. The next day he wanted to jog for 4 more minutes than the previous da
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Question 1161339: Is it B? I want to check my answer.
James decided to start exercising. The first day he jogged for 10 mins. The next day he wanted to jog for 4 more minutes than the previous day. He wanted to continue increasing by the same amount like this for every one of the days in a week.
If he succeeded in doing this how many total minutes did he run for the week?
A. 34 minutes
B. 154 minutes
C. 14 minutes
D. 90 minutes
The question is provided in the link here: https://i.imgur.com/AdSC8Bk.png
You can put this solution on YOUR website!
yes, it is B
days, each day an increase of min
if first day was, then
second day is, third ,fourth , fifth ,sixt , seventh
so, the sum of all days is
You can put this solution on YOUR website!
Is it B? I want to check my answer.
James decided to start exercising. The first day he jogged for 10 mins. The next day he wanted to jog for 4 more minutes than the previous day. He wanted to continue increasing by the same amount like this for every one of the days in a week.
If he succeeded in doing this how many total minutes did he run for the week?
A. 34 minutes
B. 154 minutes
C. 14 minutes
D. 90 minutes
The question is provided in the link here: https://i.imgur.com/AdSC8Bk.png
You're CORRECT, but I do hope you didn't calculate it the way that woman did. That method is extremely inefficient, and very time-consuming.
Somehow I just "feel" that you know that!
Sum of an A.P:
You can solve it differently and even more effectively and less time consuming.
You have an AP with the first term 10; the common difference 4; and the number of therms of 7 (one week).
You calculate the 7-th term = = 10 + 6*4 = 34;
then you calculate the average of the first and the last terms = = 22;
and finally you multiply this average by the number of the terms 7 to get the ANSWER 22*7 = 154 minutes.
You can make every step MENTALLY.
Tutor @ikleyn shows one efficient way to find the sum, knowing that it is an arithmetic sequence:
(1) use the first term and common difference to find the last (7th) term
(2) find the average of the first and last terms, which is the average of all the terms
(3) multiply that average by the number of terms.
Here is another efficient way....
(1) use the first term and the common difference to find the middle (4th) term, which is the average of all the terms
(2) multiply that average by the number of terms.