You can choose from 20 students for the first student, 19 for the second, 18 for the third, ..., 14 for the seventh student.
That gives you 20 * 19 * 18 * 17 * 16 * 15 * 14.
That number would allow you to write the students in different order. Since order here does not matter, any group with the same students in any order is the same group, you need to divide by the number of way you can order 7 items. Divide by 7 * 6 * 5 * 4 * 3 * 2 * 1
(20 * 19 * 18 * 17 * 16 * 15 * 14)/(7 * 6 * 5 * 4 * 3 * 2 * 1) = 77,520
Answer: 77,520
Let's call 'it' x. 1/2 is equal to one third of x, so we could say that 1/3x = 1/2
Now we just have a simple equation to solve:
1/3x = 1/2
x = (1/2) / (1/3)
Dividing by a rational number (such as 1/3, which is expressed in fraction form) is the same as multiplying by its reciprocal (the reciprocal of a fraction is itself when the numerator and denominator have been swapped). Therefore
x = (1/2) / (1/3) = (1/2) * 3 = 3/2 = 1.5
To check this answer, test the statement. Half is a third of x, where x=1.5:
1.5 / 3 = 0.5 = 1/2
Answer:
36 pieces
Step-by-step explanation:
4 1/8 ft x 4 1/8 ft = 49.5 in x 49.5 in = 2450.25 in^2
8.25 in x 8.25 in = 68.06 in^2
2450.25/68.06 = 36 pieces
checking for scrap loss:
49.5/8.25 = 6
so no scrap loss