Answer:
Let the speed of the train be x km/h.
Case 1:
Distance = 288 km
Speed = x km/h
Time = Distance/Speed
= 288/x h
Case 2:
Distance = 288 km
Speed = (x+4) km/h
Time = 288/x + 4 h
Since 288/x > 288/x + 4
288/x - 288/x+4 = 1
288[1/x - 1/x+4 ] = 1
[ x + 4 - x / x(x + 4) ] = 1/288
[4 / x^2 + 4x ] = 1/288
x^2 + 4x = 1152
x^2 + 4x - 1152 = 0
x^2 + 36x - 32x - 1152 = 0
x(x + 36) - 32(x + 36) = 0
(x + 36)(x - 32) = 0
x + 36 = 0 , x - 32 = 0
x = -36 , x = 32
x = -36 , rejected since speed cannot be negative.
Therefore , speed of the train = 32 km/h
Answer:
15 seconds
Step-by-step explanation:
How did i get this answer? It is apparent that the girl is capable of running 6 2/3 metres per one second and she must run 100 metres.
First, let's convert 2/3 into a decimal so that it is easier to calculate later. 2/3=0.667 (you can also just do 2 divide by 3 and will end up with the same number)
Now our numbers are 6.667 and 100. Let's divide 100 by 6.667 which estimates to 15
The two ways to find the ratio of the length is to turn the inches into feet or the feet into inches
So the answer can be solved like this:
1/36ft to 1/4ft which is 9:1 (blueprint size to actual size)
or
1/3in to 3in which is also 9:1 (blueprint size to actual size)
$33.33
20/9 = $2.22 per sheet
$2.22*15 = $33.33
he paid = 4*10 = $40
48 eggs = $40
so, waste money would be 6/48 * 100 = 12.5%