Answer:
15 black water bottles
Step-by-step explanation:
let w represent white water bottles, and let b represent black water bottles.
set up a system of equations:
w+b=20
w+2b=35
(the top equation shows that the number of white water bottles he sold and the number of black water bottles he sold equals to 20, since it says that the total number of water bottles is 20. the bottom equation shows that white water bottles cost $1, and black water bottles cost $2, and that the total amount of money he got from selling them is $35).
in the top equation, isolate w:
w+b=20
w=20-b
now we do substitution. in the bottom equation, substitute 20-b for w:
w+2b=35
20-b+2b=35
then, solve:
b+20=35
b=15
this means that he sold 15 black water bottles.
Answer:
The tree is 14 ft. tall.
Step-by-step explanation:
Height of the building/ Height of the tree = Shadow of building/ Shadow of tree
30/x = 75/35 Cross multiply
75x = (30)(35)
75x = 1050
x = 1050/75
x = 14
1. We need to get rid of all the denominator in this equation.
- This can be done by multiplying left and right sides by the LCD.
- In the problem: 12/x = 8, the LCD is X.
12/x = 8 is now 12 = x * 8
1a. 8 * x = 8x
Now, your answer is 3/2, but It's improper. Let's convert it into a mixed number.
Subtract 3 by 2.
3 - 2 = 1
3/2 = 1 1/2
Therefore, your answer is 1 1/2. Also, the answer is 1.5.