Answer:
A
Step-by-step explanation:
Answer:
37 dimes and 10 nickels
Step-by-step explanation:
let d = # dimes
let n = # nickels
we can set up a system of equations:
n + d = 47
.05n + .10d = 4.2
if we solve the first equation for 'n' we get:
n = 47-d
now we can substitute this in for 'n' in the second equation:
.05(47-d) + .10d = 4.2
2.35 - .05d + .10d = 4.2
2.35 + .05d = 4.2
subtract 2.35 from each side to get:
.05d = 1.85
d = 1.85÷.05
d = 37
if d+n = 47 and d=37 then n = 10
Check:
.05(10) + .1(37) should equal 4.2
.50 + 3.7 = 4.2 [It Checks Out]
We have been given that the upstream speed is 
and the down stream speed is 
.
Let the fisherman traveled a distance of x miles.
The total time of the trip is 6 hours.
Relations between speed (s), time (t) and distance (d) is 
Hence, 
Time upstream + time downstream = 6
lcm = 10
=> 
Cross multiplying, 
x = 20 miles .. Answer.
The dimensions of the garden that will require the least amount of fencing are 450 m and 900 m and the perimeter of the area is 1800 m.
<h3>What is the area of the rectangle?</h3>
It is defined as the area occupied by the rectangle in two-dimensional planner geometry.
The area of a rectangle can be calculated using the following formula:
Rectangle area = length x width
Let's suppose x and y are the sides of the rectangular garden and y is the parallel to the river.
Then according to the problem:
2x + y = P ..(1)
P is the perimeter of the rectangle.
xy = 405000 (area of the rectangle)
Plug the value of y in the equation (1) from the above equation.
P(x) = 2x + 405000/x
P'(x) = x—405000/x² = 0
x = 450 m
P''(x) > 0 hence at x = 450 the value of P(x) is minimum.
y = 405000/450
y = 900 m
P(min) = 1800 m
Thus, the dimensions of the garden that will require the least amount of fencing are 450 m and 900 m and the perimeter of the area is 1800 m.
Learn more about the rectangle here:
brainly.com/question/15019502
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