Answer:
Step-by-step explanation:
Let x = the number of dimes
Let y = the number of pennies.
There are 8 coins, therefore
x + y = 8 (1)
The coins are worth 17 cents, therefore
10x + y = 17 (2)
Subtract equation (1) from equation (2).
10x + y - (x + y) = 17 - 8
9x = 9
x = 1
From (1), obtain
y = 8 -x = 8 - 1 = 7
Answer: 1 dime, 7 pennies.
Answer:
B. 180°
Step-by-step explanation:
Rotate AB 180 degrees in the clockwise direction.
Answer:
Step-by-step explanation:
Amount of brine = 100 gal
amount of salt = 80 lb
rate of water running = 4 gal / min
Let A be the amount of salt in lb in the tank at any time t.
(a) dA/dt = rate of salt in - rate of salt out
Rate of salt in = 0
rate of salt out = A x 4 / 100 = A / 25 lb/min
So, dA/dt = 0 - A/25 = - A/25 lb/min
When t = 0, A = 80 lb
So,
(b) Now, A = 40 lb
So,
take log on both the sides
t = 17.3 minutes
The easiest way to think about this is to give all of the numbers common denominators:
1 can be written as 6/6
0 can be written as 0/6
Now we can see that 5/6 is only 1/6 away from 1, while it is 5/6 away from 0.
So, 5/6 is closer to 1!
