Answer:The measure of angle RST is 120\°
Step-by-step explanation:
see the attached figure to better understand the problem
we know that
m<RST=(6x+12)\° -----> equation A
m<RST=78\°+(3x-12)\° -----> equation B
equate equation A and equation B
(6x+12)\°=78\°+(3x-12)\°
1 hours is equal to 60 minutes.
2 hours = 120 minutes
40% is 120 minutes = 120*40/100 = 48 minutes
A + s = 279
s = 2a
a + 2a = 279
3a = 279
a = 279/3
a = 93 <=== adult
s = 2a
s = 2(93)
s = 186 ....students