If one star equals four circles and three circles equal four diamonds, then what is the ratio of star to diamond? `1:3` b. `3:4` c. `3: 16` d. `16 :3`

If the perimeter of circle A is equal to perimeter of semi circle B, what is the ratio of their areas ?

The circumferences of two circles are in the ratio 3:4. The ratio of their areas is 3:4 (b) 4:39:16(d)16:9

The radii of two circles are in the ratio 2:3. The ratio of their areas is (a) 2:3 (b) 4:9 (c) 3:2 (d) 9:4

From a circular sheet of paper with radius 20 cm, four circles of radius 5 cm each are cut out. What is the ratio of the uncut to the cut portion? (a) 1 : 3 (b) 3 : 1 (c) 4 : 1 (d) 4 : 3

Five mangoes and four oranges cost as much as three mangoes and seven oranges.What is the ratio of the cost of one mango to the cost of one orange? 4:3 b.1:3 c.3:2 d.5:2

If the four equal circles of radius 3 cm touch each other externally, then the area of the region bounded by the four circles is

ABCD is a square, in which a circle is inscribed touching all the sides of square. In the four corners of square 4 smaller circles of equal radii are drawn, containing maximum possible area. What is the ratio of the area of larger circle to that of sum of the areas of four smaller circles? (a) 1 : (68 - 48 sqrt2) (b) 1 : 17 sqrt2 (c) 3 : (34 - 12 sqrt2) (d)None of these

If the refractive index of diamond is 2.4 find the velocity of light in diamond.(c= 3xx10^(8) m/s)

The volumes of two spheres are in the ratio of 64 : 27. The ratio of their surface areas is (a) 1 : 2 (b) 2 : 3 (c) 9 : 16 (d) 16 : 9