Answer:
351.68 cm^2
Step-by-step explanation:
We need to find the area of the frame itself. the radius of the inner circle is 12, but the frame has a radius of 4. You add 12 and 4 and you get 16. The formula for area of a circle is A=πr^2. So A= 3.14 x16^2. Then you have A= 3.14x 256 and you get 803.84. But we only want the area of the frame, so you have to get the area of the inner circle and subtract. You get A= 3.14 x 12^2. 3.14x144 is 452.16. 803.84-452.16 is 351.68. Hope this helped. :)
So he used 0.33 L of milk to make 0.11 L of tea
Answer:
7 square units
Step-by-step explanation:
As with many geometry problems, there are several ways you can work this.
Label the lower left and lower right vertices of the rectangle points W and E, respectively. You can subtract the areas of triangles WSR and EQR from the area of trapezoid WSQE to find the area of triangle QRS.
The applicable formulas are ...
area of a trapezoid: A = (1/2)(b1 +b2)h
area of a triangle: A = (1/2)bh
So, our areas are ...
AQRS = AWSQE - AWSR - AEQR
= (1/2)(WS +EQ)WE -(1/2)(WS)(WR) -(1/2)(EQ)(ER)
Factoring out 1/2, we have ...
= (1/2)((2+5)·4 -2·2 -5·2)
= (1/2)(28 -4 -10) = 7 . . . . square units
Answer: 16 + 200 = 216
Step-by-step explanation: