For an instance, g represents the original amount of girls and b represents the original amount of boys.
Write an equation based on the problem
There was 40% girls, the equation will be
g = 40% (b + g)
<span>first equation
</span>
If two girls left and two boys came, there was 30% girls, the equation will be
g - 2 = 30%(b + 2 + g - 2)
<span>second equation
</span>Work on the first equation
To make it easier in calculation, change percent into decimals
g = 40% (b + g)
g = 0.4(b + g)
g = 0.4b + 0.4g
Work on the second equation
Change percent into decimals and simplify the equation
g - 2 = 30%(b + 2 + g - 2)
g - 2 = 0.3(b + g)
g = 0.3b + 0.3g + 2
Solve the equation system by substitution method
g = g
0.4b + 0.4g = 0.3b + 0.3g + 2
0.1b + 0.1g = 2
0.1(b + g) = 2
b + g = 20
The original amount of boys and girls is 20
Find the original amount of girls
Original amount of girls is equal to 40% of the original amount of boys plus girls.
g = 0.4(b + g)
g = 0.4(20)
g = 8
The original amount of girls is 8
Answer:
27.2 ft
Step-by-step explanation:
Let's set up a ratio that represents the problem:
Object's Height (ft) : Shadow (ft)
Substitute with the dimensions of the 34 foot pole and its 30 foot shadow.
34 : 30
Find the unit rate:
The unit rate is when one number in a ratio is 1.
Let's make the Shadow equal to one by dividing by 30 on both sides.
Object's Height (ft) : Shadow (ft)
34 : 30
/30 /30
1.13 : 1
Now, let's multiply by 24 on both sides to find the height of the tree.
Multiply:
Object's Height (ft) : Shadow (ft)
1.13 : 1
x24 x24
27.2 : 24
Therefore, the tree is 27.2 feet tall.
This is gonna be the answer. It’s 4+sqrt(19) and 4-sqrt(19). Which is approximately 8.36 and -0.36. In x intercept form, it’s (8.36,0) and (-0.36,0) also I solved this by completing the square. I hope this helps!!! Mark as brainliest!!!
Answer:
14
Step-by-step explanation: