As you want a 60% discount, you must find 40% of $12.25.
40% of $12.25 is the same as 2/5 of $12.25.
Now, 12.25 / 5 = 2.45
And, 2.45 x 2 = 4.90
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This means that 60% off $12.25 is $4.90.
25 that how much she will need
Step-by-step explanation:
Draw diagonal AC
The triangle ABC has sides 17 and 25
Say AB is 17, BC is 25
Draw altitude on side BC from A , say h
h = 17 sin B
Area = 25*17 sin B = 408
sin B = 24/25
In ∆ ABC
Cos B = +- 7/25
= 625 + 289 — b^2 / 2*25*17
b^2 = 914 — 14*17 = 676
b = 26
h = 17*24/25 = 408/25 = 16.32
Draw the second diagonal BD
In ∆ BCD, draw altitude from D, say DE =h
BD^2 = h^2 + {(25 + sqrt (289 -h^2) }^2
BD^2 = 16.32^2 + (25 + 4.76)^2
= 885.6576 + 266.3424
BD = √ 1152 = 33.94 m
Answer:
6.78ft/sec
Step-by-step explanation:
From the question, dx/dt= 3.9 ft/sec
We are looking for Dy/dt
From geometry,vof this case the relationship between x and y is needed here, there is two similar triangle that exhibited by the man and the lamb
12/y= 5.1/(y-x)
Then ,cross multiply, we have
12(y-x)=5.1y
12y-12x=5.1y
12y-5.1y=12x
6.9y=12x
y=( 12/6.9)x
Differentiating implicitly the bother sides with respect to t, we have
Dy/dt= ( 12/6.9)dx/dt
But dx/dt= 3.9 ft/sec
Then Dy/dt= ( 12/6.9)× 3.9
Dy/dt=6.78ft/sec
Hence, the rate that the tip of the person's shadow moves away from the lamppost when the person is 9 ft away from the lampost is 6.78ft/sec
CHECK THE ATTACHMENT FOR THE FIQURE