Answer:
8 rabbits
22 chickens
Step-by-step explanation:
c = chickens
r = rabbits
heads - c + r = 30
legs - 2c + 4r = 76
We can now use these two equations to create one by isolating the variable (c) in the first equation.
c = 30 - r
2c + 4r = 76
2(30 - r) + 4r = 76
60 - 2r + 4r = 76
2r = 16
r = 8
Now we know that there are 8 rabbits, which means that there has to be 22 chickens in order to have 30 heads.
What do you not understand
Answer:
There are 400 possible zip codes in the Houston area
Step-by-step explanation:
Here, we want to calculate the possible number of zip codes in the Houston area
We have 5 digits to form
77 is the first two digits ( this is fixed)
For the third digit, we are selecting 1 number out of 0,3,4 or 5
This means 4 C 1
The remaining digits can be any digits
We have 0-9, a total of 10 digits
The first will be 10 C 1 and the second last digit too is 10 C 1
So the number of possible zip codes will be;
4 C 1 * 10 C 1 * 10 C 1
= 4 * 10 * 10 = 400 possible zip codes
Answer:
14 * 8 = money given out
Step-by-step explanation:
#of people given money * (times) amount per person.
We can use trial or error method here...
If we take 4 table, 4*5 = 20 and 4*7 = 28. 20+28 = 48.
20 : 28 = 5 : 7
So, there are 20 boys and 28 girls in a school play and there are 8 girls more than boys.
If you look over tables and try it out, only 4 table works for the given ratio.