Answer:
19.5
Step-by-step explanation:
78÷4
=39÷2
=19.5
The Answer is 19.5
The answer would be D if it was 250-6-3n. it wouldnt be A or C because 9 isnt anywhere in the problem and it wouldnt be B because she used 6 peices of paper she didnt just give it to her students
Answer:
66 ≤ f ≤100
Explanation
Mean= ( Σ x ) / n
Mean= sum of scores/ number of subject she took
Now, she already too 3 subject which sum is 85+83+86=254
Now we need to know range of score for her to have (grade) a mark between 80 and 89
Now let take the lower limit mean=80
The lowest score she can get is
Mean = ( Σx) / n
80=(85+83+86+f)/4
80×4= 254+f
Therefore, f= 320-254=66
Therefore the minimum score she can have to have a B is 66.
Then, let take the upper limit mean 89. i.e the maximum she can have so that she don't have an A grade.
Mean = ( Σx) / n
89=( 83+85+86+f)/4
89×4= 254+f
f= 356-254
f=102.
Therefore this shows that she cannot have an A grade in the exam. The maximum score for the exam is 100.
There the range of score is 66 ≤ f ≤100 to have a B grade
66 ≤ f ≤100 answer
Since she cannot score 102 in the examination.
Answer:
The height of near by tree will be 90 feet.
Step-by-step explanation:
Considering the water triangle as shown in figure a.
As the old faithful shoots water 60 feet into the air that casts a shadow of 42 feet.
Considering the tree triangle as shown in figure a. The tree triangle has a shadow 63 feet long.
Let x be the height of near by tree that cost a shadow 63 feet long.
Assuming that the triangles are similar
So,
the ratios of similar triangles will be related as:




feet
Therefore, the height of near by tree will be 90 feet.
Keywords: ratio, similar triangle
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