I believe the correct answer is D.
Answer:
there are 70 possible choices for the four locations to apply the new ointment
Step-by-step explanation:
Since we have a total of 8 locations ( 4 to the new ointment and 4 to the control) , each one can be chosen and since the order of the locations that are chosen for the new ointment is not relevant , then we know that the number of choices is given by the number of combinations of 4 elements in 8
number of combinations = 8 possible locations to the first ointment * 7 possible locations to the second ( since the first one was already located) * 6 to the third * 5 locations for the fourth / number of times the same combination is repeated ( the same locations but in different positions) = 8*7*6*5 / (4 possible positions for the first ointment* 3 possible positions to the second ointment (since the first one was already located * 2 possible positions of the third * 1 possible position of the fourth)
therefore
number of combinations = 8*7*6*5/(4*3*2*1 ) = 8!/((8-4)!*4!) = 70 possible combinations
thus there are 70 possible choices for the four locations to apply the new ointment
58=7/4x
Multiply both sides by 4 so the fraction cancels out:
232=7x
Divide both sides by 7:
x=33.14 (rounded)
Hope this helps :)
Answer:
C) 21 girls : 9 boys
Step-by-step explanation:
You just have to compare the ratio you're given to the answers and see if the ratios from the answers match up to the ratio you were given. The reason C is the answer is because if you divide by 3 in the ration, it is the same as the ratio you were given, 7:3
It will take 6.875h for the second car to overtake the first...
