40$ - 100% (full price)
x$ - 70% (100-30=70%)
40 * 70 = 100x
2800 = 100x
x = 28
Answer 28$
or
40$ = 100%
then 1% = 40/100 = 0.4$
so 70% will be 0.4 * 70 = 28$
Answer:

Step-by-step explanation:
Find two numbers whose quotient is -1 and the subtraction of the first minus the second is -3/2
Let two numbers are x and y. When they are divided the quotient is -1. So,

It can also be written as :
x = -y ....(1)
The subtraction of first minus the second is -3/2
.

Use equation (1) in (2),

From equation (1) : 
Hence, two numbers are
.
We move the decimal point to the left by five figures to get 0.0000845
C. 300 ft.2 and <span>d. 81π in.3</span>
From 3 oranges to 4 oranges, you're adding 45¢. Therefore, 1 orange is 45¢. You can then multiply 45 by 10 to get 450¢, which is $4.50. $4.25 is less than $4.50, so not following the pattern is cheaper. Hope this helps!