2/5=6/15 and that is less than 7/15
Answer:
Step-by-step explanation:
Comment
If two secants intersect outside a circle (as these two do) then the angle at which they meet is 1/2 the difference between the intersected arcs. Put much simpler <DCF = 1/2 (arc EG - arc DF)
Givens
Arc EG = 127
Arc DF = 49
Solution
<DCF = 1/2(127 - 49)
<DCF = 1/2(78)
<DCF = 39
If the radiation level is 100%, it would take 2.4 days to take the radiation level to 50%. However, the situation implies that the radiation level is 25% only, so we need to take 25% from 2.4 days to know the timeframe for a room to be emptied from the radioactive gas. 2.4 days multiplied by 0.25 will give a result of 0.6 day - the timeframe needed to empty the room out of the radioactive gas.