Ratio more red counters

Question

There are some red counters and some yellow counters in a bag.

There are 30 yellow counters in the bag.

The ratio of the number of red counters to the number of yellow counters is 1:6

Riza puts some more red counters into the bag.

The ratio of the number of red counters to the number of yellow counters is now 1:2

How many red counters does Riza put into the bag?

 

 

Answer 1

If there are 30 yellow "counters" and # red: # yellow = 1:6,

that means: # red /30 = 1/6.  Therefore the # of red counters is 5 and there are 25 yellows.

 

Now after the addition of x red counters, # red: # yellow = 1:2.

(5+x):30 = 1/2.

 

This leads to x = 10 (additional reds).

 

Answer 2

There is one red counter for every 6 yellow counters.

 

30 = 6 = 5, there fore there were 5 red counters in the bag.

 

There are still 30 yellow counters in the bag plus five red counters. To get a ratio of 1 red counter for every 2 yellow counters, you have to have a total of 15 red counters in the bag. Since five are already there, you must add 10 red counters.

 

Kenneth S. changed the number of yellow counters to 25, but 30 is given as the number of yellows.