To answer this you can use a guess and check strategy.
Start with 5 minutes using it (25% lost) and 10 minutes charging (20% gained).
Try 7 minutes using it (35% lost) and 14 minutes charging (28%).
Next, 9 minutes (45%) and 18 minutes(36%).
10 minutes (50%) and 20 minutes (40%). This is the difference.
She used it for 10 minutes and charged it for 20 minutes.
Very interesting question!
Let's try to get something that would work for just 5 for now.
Any of these numbers would leave a remainder of 1 when divided by just 5:
6, 11, 16, 21, 26, 31, 36, 41, 46, 51, 56, 61, 66, 71, 76, 81, 86, ...
Notice that they all look like 5*(something) + 1. Basically, they are all multiples of 5 plus 1.
Let's see what would work for just 8:
9, 17, 25, 33, 41, 49, 57, 65, 73, 81, 89, ...
Are there any matches... AHA! It's 81. This is the lowest positive integer greater than 1 that follows the rule for both 5 and 8.
It`s either 100,000 because there is only four 0`s making it 70,000 or it`s 700,000 and you made a mistake of not typing that last zero in which case the question would be pointless to ask because the answer is in the question.
(4x20)+30=$110 taken out. if he had $96 put back in, then go $110-$96, leaving a balance of -$14, or in other words, the balance dropped $14.
Answer:
1002
Step-by-step explanation:
171x6=1026
171×2=342
1026-342=684
684+318=1002