Answer:
surface area of the triangular pyramid
=(1/2×9×7.8)+(3×1/2×9×12.3)
=35.1+166.05
=201.15 inch²
Answer:

Step-by-step explanation:
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Answer:

Step-by-step explanation:
Given: Perimeter of triangle= 72 units
Measure of one of the side= x units
Measure of second side = 3x units
We know the perimeter of triangle is equal to sum of all sides.
Now, finding the possible value of x
forming an inequality to determine the value of x
Remember triangle has three sides, however, measure of only two sides are given.
⇒ 
⇒ 
Dividing both side by 4
⇒ 
∴ The inequality to represents all possible values of x is 
Standardising X=71 to find z-score

reading from z-table

Students score below 71 is 84.13%