#Lutece1668. Drinks
Drinks
Migrated from Lutece 1668 Drinks
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Description
Every weekend, and play in the park, and for each time, one of them has to buys drinks for both. They agree to apply the following procedure to determine who is on the duty of buying drinks.
.Put red balls and white balls in a paper bag.
. and draw a ball from the bag in turns. Note that once a ball is drawn, it is removed from the bag.
.The person who draws a red ball first has to buy drinks.
lets perform the first draw every week for is older than him. One day, suddenly wonders what is the probability that he draws a red ball first. Can you help him to calculate it? You may assume when every ball has the same probability to be drawn
Input
The first line contains a positive integer , , indicating the number of test cases. Each test case has one line contains two positive integers and where , and . is the number of red balls, and is the number of white balls.
Output
For each test case, output one line containing the answer represented by a reduced fraction.
Samples
2
1 1
1 2
1/2
2/3
Resources
Taiwan > TOPC 2015 Problem D