can anyone help???

[swapna]

A laboratory has 55 rabbits,some white and the rest brown. Which of the following could be the ratio of white rabbits to brown rabbits in the lab??
1:3
3:8
5:11
3:4
5:1

ans b..can some one explain??

[papgust]

55 rabbits are in the ratio of whites to browns.

The best method to solve is to use the answer choices.

In B, when you have 3:8, it means that there is some common number between the ratio - consider 'x'. Sum of 3x and 8x must equal total number of rabbits.

3x+8x = 55
11x = 55

'x' must be an integer because you are calculating the number of rabbits (which should be an integer). So, B is the only choice that divides 55 equally.

[swapna]

thanks...got it...that was pretty quick:-)

[sanju09]

A laboratory has 55 rabbits,some white and the rest brown. Which of the following could be the ratio of white rabbits to brown rabbits in the lab??
1:3
3:8
5:11
3:4
5:1

ans b..can some one explain??

Since the number of rabbits in each group for all intents and purposes is a positive integer, the sum of ratio numbers must be a factor of 55, and only [spoiler]3:8[/spoiler] is one such ratio in the choices.

[spoiler]B[/spoiler]