If the numbers after the decimal terminate, yes, it's rational.
9.521521521 = 9,521,521,521 / 1,000,000,000
If they don't terminate, but the pattern continues (which I suspect is the case here), yes, it's still rational.
If <em>x</em> = 9.521521521…, then
1000<em>x</em> = 9521.521521521…
Subtract <em>x</em> from this to eliminate the fractional part:
1000<em>x</em> - <em>x</em> = 9521.521521521… - 9.521521521…
999<em>x</em> = 9512
<em>x</em> = 9512/999
If they don't terminate, but the pattern does <em>not</em> continue, meaning the next few digits could be something random like
9.521521521<u>19484929271283583457</u>…
then the number would be irrational.
Each individual contributed $x
3x=$19.50
x=$6.50
Each friend contributed $6.50
Step-by-step explanation:
we assume day and night are equally long.
and the mouse will start at night of day 1.
then, on day 2, it will first retreat 2 meters (during daylight) and then advance 14 meters (at night).
so, on every full day, the mouse will effectively advance 12 meters (-2 + 14 = 12).
with a starting value of 14 (the first night).
so, we are getting an arithmetic sequence
an = an-1 + c
c = 12 in our case.
a1 = 14
a2 = a1 + 12 = 14+12 = 26
a3 = a2 + 12 = a1 + 12 + 12 = 14 + 2×12 = 38
an = a1 + (n-1)×12 = 14 + 12(n-1)
at what n will it reach 86 ?
86 = 14 + 12(n-1) = 14 + 12n - 12 = 2 + 12n
84 = 12n
n = 7
so, on the 7th day the mouse will reach the surface (if we truly count the first starting night day 1 - this is up to your teacher, but I would).
2.00 * 8.5%, which is also 2.00 * 0.085
2.00 * 0.085 = 0.17
2.17 after sales
