Answer:
$10 coins: 21
$20 coins: 24
Step-by-step explanation:
heyy me again
So we can create 2 equations where
x = number of $10 coins
y = number of $20 coins:
x + y = 45
10x + 20y = 690
we can move equation 1 around so that we can get a value of x
x = 45 - y
now we can substitute x into the second equation
10(45 - y) + 20y = 690
450 - 10y + 20y = 690
10y = 240
y = 24
Now plug in y back into the first equation
x = 45 - y
x = 45 - 24
x = 21
Answer:
Mai lives 384 miles away from the mountains
Step-by-step explanation:
Let d represent distance between Mai's house and mountains and r represent Mai's rate while going to mountains.
We have been given that there was heavy traffic on the way there, and the trip to mountains took 8 hours.


We are also told that when Mai drove home, there was no traffic and the trip only took 6 hours. Her average rate was 16 miles per hour faster on the trip home.

Upon equating equation (1) and equation (2), we will get:






Upon substituting
in equation (1), we will get:

Therefore, Mai lives 384 miles away from the mountains.