12 is 60% of 20. You can make 60% into a fraction (60/100) and set that fraction equal to 12/x. You then cross multiply (12*100 and 60*x) to get 1200=60x. You then divide both sides by 60 to get x, which equals 20.
Answer:
The difference between the total and lateral surface areas of the room is 42 square yards.
Step-by-step explanation:
The lateral surface area of an object is the surface area of everything EXCEPT for the top and bottom of the object.
2(6*4.2) + 2(4.2*3.5) = 79.8 square yards
The total surface area of an object is everything INCLUDING the top and bottom of the object.
79.8 + 2(6*3.5) = 121.8 square yards
121.8 - 79.8 = 42 square yards
Answer:
One year ago, he had height of 150 cm.
Step-by-step explanation:
We have to model this situation.
The first step is having everything as the same unit. I am going to work in meters initially.
Each m is 100 cm. So 10cm = 10/100 = 0.1m.
I am also going to say that his height one year ago was x.
His height is now 1.6m, which is 10cm = 0.1m above his height last year, which was x. So



His height last year was 1.5m.
In centimeters, that is 1.5*100 = 150 cm.
A) 4*N -Q = 0
B) .05N + .25Q = 2.10
Multiply B) by 4
B) .2N + Q = 8.40 Adding this to A)
A) 4*N -Q = 0
4.2N = 8.40
N = 2 Nickels
Q = 8 Quarters