Answer:
91.72% likely that the soil sample contains organic matter.
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
We have that:
Of 700 samples that contain organic matter, 665 give a positive result and 700 - 665 = 35 give a negative result.
Of 300 samples that do not contain organic matter, 300 - 240 = 60 give a positive result and 240 give a negative result.
If a soil sample test gives a positive result, it is ___% likely that the soil sample contains organic matter.
665 with organic matter out of 665 + 60 = 725 positive tests.
665/725 = 0.9172
0.9172*100% = 91.72%.
91.72% likely that the soil sample contains organic matter.
