Answer:
45
40 percent (calculated percentage %) of what number equals 18? Answer: 45.
Jeff received 280$ from his mother
Such questions are the simplest as it needs you to just write the conditions accordingly which then simplifies and provides you the answer.
This question can be solved using two tricks which are shown below:-
Trick 1 :
1 – 1/4 = 3/4 (used for the 1st 7 days)
1/4 – 410 (used for 8th and 9th days)
(3/4)/7 ——- (1/4 – 10)/2
(3/4) x (2/7) = 3/14 ——- (1/4 – 10)
1/4 – 3/14 = (7 – 6)/28 = 1/28 ——- 10
28/28 ——- 10 x 28 =$ 280
Trick 2 :
7 days ——- 3/4
1 day ——- 3/28
2 days ——- 6/28
6/28 ——- (1/4 – 10) = 7/28 – 410
1/28 ——- 10
28/28 ——- 10 x 28 = $280
Thus Jeff received 280$ from his mother.
Learn more about simple math here :
brainly.com/question/23678
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Amphitrite1040Answer:
Amphitrite1040
Step-by-step explanation:
If f(x)=x^2-8x-20 then
dy/dx=2x-8 and d2y/dx2=2
A) Since acceleration is a constant positive the parabola opens upward.
B) Since acceleration is a constant positive the parabola will have a vertex at an absolute minimum
C) The vertex will occur when dy/dx=0, 2x-8=0, 2x=8, x=4
So the axis of symmetry is the vertical line x=4.
The vertex is y(4)=-36, corresponding to the vertex point (4,-36)
The y-intercept occurs when x=0, y(0)=-20, so the y-intercept is the point (0,-20)
D is the correct answer. To find this, take the total number, 25 and multiply it by 19% to get 21, which is the number of hard copies.
