Answer:
Prob.3
Denote r: radius of circle O
Formula for calculating AOB sector:
Area = pi*r^2*angle/360
Area = pi*r^2*45/360 = 18 pi
=> r^2 = 18*360/45 = 144
=> r = 12
For prob.4, give it a try, follow the formula I gave. Good luck !
(answer : r = 6)
Answer:
less
Step-by-step explanation:
An increase of 20% makes the price 120% of the original price.
A discount of 20% makes the discounted price 80% of the previous price.
Original price: x
20% increase in price: 1.2 * x
20% discount over the raised price: 0.8 * 1.2 * x
Now we multiply the numbers in the last expression and compare the result with x.
0.8 * 1.2 * x = 0.96x
0.96 is less than x, so the customer pays less than the original price.
your answer would be -2.57142857143
Answer:
1. Rate needed 9/6; Unit rate is 1.5/1; 1.5 cans of white paint are needed for each can of blue.
2. rate needed = 12/6; unit rate = 2/1; Need 2 cups of water for every scoop of fruit mix.
3. 70 minutes
Step-by-step explanation:
1. Set up a ratio
3white/2blue = xwhite/6blue
3/2 = x/6
cross multiply 2x = 18; x = 9
rate needed = 9/6
Unit rate is 1.5/1 (divide 3 by 2 or 9 by 6 to get unit rate_
2. 3/1.5 = x/6
1.5x = 18; x = 12
rate needed = 12/6
unit rate = 2/1
3. Set up a ratio.
3.5/.25 ( 1/4=.25)
3.5/.25 = x/5
.25x = 3.5(5)
.25x = 17.5
x = 70 minutes
