Her average in first three test = 89
This means, her total scores in first three test were = 3 x 89 = 267
Her average in four tests = 91
This means, her total scores in four tests are = 364
267 give the sum of first three test scores. and 364 give the sum of scores with fourth test adding in three tests.
So, subtracting 267 from 364 will give us the scores of Fourth test.
Scores of Fourth test = 364 - 267 = 97
Thus, Samantha's Claim is correct
Answer:
a horizontal line
Step-by-step explanation:
The hyperbola opens vertically, so the directrix is a horizontal line (a different one for each branch).
Convert 
to exponential/polar/trigonometric form:
By DeMoivre's theorem,
so that 
and 
.
Tami thought that the perimiter is length plus width, which gave her 100. The actual width is 20
Answer:
32.4kg
Step-by-step explanation:
if it loses one tenth of cement;
36kg×1/10
36kg/10
3.6kg was lost
to find the remaining ; 36kg - 3.6kg = 32.4kg is left in the bag
