Answer:
He have 43 bills of 10 and 13 bills of 5
Step-by-step explanation:
5x + 10y = 495
x + y = 56
Isolate x:
x = 56 - y
Substitute in the first equation:
5(56 - y) +10y = 495
280 -5y +10 y = 495
5y = 495 -280
5y = 215
y = 215/5
y= 43
Now substitute the value of y to find x:
x = 56 - y
x = 56 - 43
x = 13
Answer:
310%
Step-by-step explanation:
Convert the fraction to a decimal, then multiply by 100.
R=rate of boat in still water
c=rate of current
d=rt
since you're given that the time it takes to travel the same distance downstream and upstream, your equation will be d_1=d_2, or rt=rt
the rate upstream is r-c and the rate downstream is r+c (because the boat's and river's rates add up)
since you know t_1 and t_1 are 5 and 3, you can now set up 2 equations
<u>5*(r-c)=45</u> because (time upstream)*(rate upstream)=distance=45 miles
r-c=45/5=9
<u>3*(r+c)=45</u>
r+c=45/3=15
r-c=9 and r+c=15, so r=12 mi/h and c=3 mi/h
If you have any questions please ask
Answer:
7.1 weeks to 68.4 weeks
Step-by-step explanation:
Chebyshev's Theorem states that:
75% of the measures are within 2 standard deviations of the mean.
89% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 38.1
Standard deviation = 10.1
Between what two search times does Chebyshev's Theorem guarantee that we will find at least 89% of the graduates
Between 3 standard deviations of the mean.
So from 38.1 - 3*10.1 = 7.8 weeks to 38.1 + 3*10.1 = 68.4 weeks
1. 15
2. 5
3. Flashcards
Pretty sure this is right, good luck!