Study the given table and answer the question that follows.

The table shows the number of students studying in six different classes of six different schools.

School	Class V	Class VI	Class VII	Class VIII	Class IX	Class X
P	152	160	145	156	147	144
Q	148	166	150	155	157	143
R	161	152	140	145	143	165
S	159	142	149	140	142	168
T	147	144	158	163	154	150
U	150	160	162	160	161	140
Total	917	924	904	919	904	910

What is the respective ratio of students studying in class IX of schools Q and R together to those studying in class VI of schools S and T together?