Answer:
100
Step-by-step explanation:
In this problem 10 represents 9% of a number. So, to find 90% you must multiply 10 by 10. You do this because 9% times 10 equals 90%; therefore, 100 must be 90%.
This can also be proven through cross multiplication. To set up a proportion put the percent over the number like, 
. Then cross multiply to get the equation, 
. Finally, divide both sides to get x=100.
9514 1404 393
Answer:
after 7 minutes
19,600 feet
Step-by-step explanation:
Here's the "pencil and paper" solution:
The two altitude equations are ...
y = 41300 -3100x
y = 2800x
They can be solved by setting the expressions for y equal to each other.
2800x = 41300 -3100x
5900x = 41300
x = 41300/5900 = 7
y = 2800·7 = 19600
The planes will both be at 19,600 feet after 7 minutes.
You find the x coordinates using x = -b/2a = -6/2(-1) = 3
Substitute 3 in the equation and find y
y = -(3^2) + 6(3) - 12 = -9 + 18 - 12 = -3
Vertex (3,-3)
Answer:
Step-by-step explanation:
EXAMPLE #1:
What number is 75% of 4? (or Find 75% of 4.)
The PERCENT always goes over 100.
(It's a part of the whole 100%.)
4 appears with the word of:
It's the WHOLE and goes on the bottom.
A proportion showing one fraction with PART as the numerator and 4 as the denominator equal to another fraction with 75 as the numerator and 100 as the denominator.
We're trying to find the missing PART (on the top).
In a proportion the cross-products are equal: So 4 times 75 is equal to 100 times the PART.
The missing PART equals 4 times 75 divided by 100.
(Multiply the two opposite corners with numbers; then divide by the other number.)
4 times 75 = 100 times the part
300 = 100 times the part
300/100 = 100/100 times the part
3 = the part
A proportion showing the denominator, 4, times the diagonally opposite 75; divided by 100.
Answer:
4
Step-by-step explanation:
65-25=40
40/10=4
