Answer:
<h3>50m</h3>
Step-by-step explanation:
Given the dimension
Length of the rectangle = 8cm
Width = 5cm
Note that when the scale was 1:7, syla multiplied the width by a factor of 7 i.e 5*7 = 35m
If syla changes the the scale to 1 cm : 10 m for the rectangle, then the width of the shorter side will be multiplied by a factor of 10 due to the change in scale i.e;
5 * 10 = 50m
Hence the width of the new stage will be 50 m
This kind of problems are solved using Bernoulli's distribution. Everytime you have a win/lose scenario, and you know the probability
of winning, and you want
successes over
trials, you have the following probability:

You want the probability of having at least three successes, i.e. you are interested in the cases k=3 and k=4. The corresponding probabilities are


So, the total probability is 
Comparing x-1 with x-a then x=1
1^3+p*1^2-1-2=0
1+2p-3=0
2p=3-1
P=2/2
P=1
:.p=1
To solve this, you must find out the total amount of envelopes she has, and the number of envelopes she has already mailed out. One equation that can work is:
140≥26+x or 140=26+x
X represents how many more envelopes she must mail out still
And you must use the ≥ or = symbol because 140 is the total amount of envelopes she has. She doesn’t have more than 140, 26+x must be equivalent to 140, or 140 must be greater or equal to 26+x.
Hopefully this made sense : )