Answer
18 hours
Step-by-step explanation:
if 10 people spend 15 hours
one person spend 15/10=1.5
so 1.5 × 12=18hours
Answer:
D
Step-by-step explanation:
EXPLORE test is the college test ACT's "prep" version mostly for 8th and 9th graders.
ASVAB (Armed Services Vocational Aptitude Battery) test is used for military entrance exam.
PLAN is also like EXPLORE that it is a "prep" test for ACT but usually given to sophomore (10th grade) students. This has been discontinued from 2014, though.
SAT is a standardized test administered by College Board and is a widely used common Undergraduate University admissions exam. Colleges use this to make admissions decisions.
Thus, D is the correct choice.
Answer:
The tabulated value is less than the calculated value, therefore we accept the null hypothesis and It show that there is a difference in the mean overall distance of brands.
Step-by-step explanation:
7 1/5 - 2 3/5 =
36/5 - 13/5 =
23/5 or 4 3/5 <==
1.8, Problem 37: A lidless cardboard box is to be made with a volume of 4 m3
. Find the
dimensions of the box that requires the least amount of cardboard.
Solution: If the dimensions of our box are x, y, and z, then we’re seeking to minimize
A(x, y, z) = xy + 2xz + 2yz subject to the constraint that xyz = 4. Our first step is to make
the first function a function of just 2 variables. From xyz = 4, we see z = 4/xy, and if we substitute
this into A(x, y, z), we obtain a new function A(x, y) = xy + 8/y + 8/x. Since we’re optimizing
something, we want to calculate the critical points, which occur when Ax = Ay = 0 or either Ax
or Ay is undefined. If Ax or Ay is undefined, then x = 0 or y = 0, which means xyz = 4 can’t
hold. So, we calculate when Ax = 0 = Ay. Ax = y − 8/x2 = 0 and Ay = x − 8/y2 = 0. From
these, we obtain x
2y = 8 = xy2
. This forces x = y = 2, which forces z = 1. Calculating second
derivatives and applying the second derivative test, we see that (x, y) = (2, 2) is a local minimum
for A(x, y). To show it’s an absolute minimum, first notice that A(x, y) is defined for all choices
of x and y that are positive (if x and y are arbitrarily large, you can still make z REALLY small
so that xyz = 4 still). Therefore, the domain is NOT a closed and bounded region (it’s neither
closed nor bounded), so you can’t apply the Extreme Value Theorem. However, you can salvage
something: observe what happens to A(x, y) as x → 0, as y → 0, as x → ∞, and y → ∞. In each
of these cases, at least one of the variables must go to ∞, meaning that A(x, y) goes to ∞. Thus,
moving away from (2, 2) forces A(x, y) to increase, and so (2, 2) is an absolute minimum for A(x, y).
