No More Hapalies!#95
In a distant land, there is a university named the University of Impartiality (UI). This is a fictional institution, and you should not associate it with any real university. Almost all of UI's students (or at least most of them) are active, creative individuals with bright futures. Unfortunately, Hapaly was not one of them, as he never tried to make proper use of his abilities.
At the start of a new term, Hapaly visited the UI academic office to obtain an official certificate showing his overall average over all previous terms (i.e., the weighted average of all his course grades), which he needed to submit to a government office. A woman at the desk told him, "Not all grades from the last term have been entered into the computer yet (as sometimes happens at real universities), so it's better if you come back tomorrow," as she continued her phone call. Hapaly thought it might be useful to find out his remaining grades and convinced a local ACM/ICPC problem setter to create a problem based on his situation.
The woman told him: "Your overall average and the total credits earned before the last term (that is, excluding last term's grades) are and respectively," as she tried to continue her call. Hapaly remembers his last term: he earned credits with an average grade of during the last term. Now Hapaly needs your help to calculate his current overall average, including the last term.
The first line contains a single integer — the number of test cases.
Each of the following lines describes one test case and contains four numbers: , , , — the total number of credits earned before the last term (0 \leq T \leq 200), average grade before the last term (0.00 \leq A \leq 20.00), number of credits in the last term (0 \leq N \leq 200), and the average grade in the last term (0 \leq M \leq 20.00). All numbers are separated by spaces.
For each test case, print Hapaly's current overall average, including the last term, formatted to exactly two digits after the decimal point, one per line.
Example 1