Answer:
1. 54 and 9/20 km
2. 80 mm
3. 1.142 mi
4.0.83333 cm
Step-by-step explanation:
Do them all by the butterfly method.
The length of the picture would be 10 inches. If the frame needs to be 34, that means 7+7 for the width and 10+10 for the length.
I have attached an image explaining how to solve this problem.
(“m” means slope)
Answer:
There will be 200 000 bacteria after 8 hours
Step-by-step explanation:
The crop quadruples every hour.
x represents the number of hours that pass after preparing the crop
y represents the number of bacteria after x hours.
The equation for y in function of x 3 hours after observing the crop is:

We want to know after how long there will be 200 000 bacteria.
Then we make y = 200 000 and clear x.

Answer:
x=8
Step-by-step explanation:
If the value of x varies directly as the value of y we can say they are directly proportional. This implies that when y increases x will increase too, and when y decreases x will also decrease.
If x=16 when y=3/4 we can write their relation as:
x/y = 16/(3/4) = 16*(4/3) = 64/3
So, for every value of y, the ratio x/y must maintain equal to 64/3 because both values are proportional.
Now we can see what happens to x when y varies. If y=3/8:
x/(3/8) = 64/3
Multiply both sides by 3/8 to eliminate the 3/8 in the denominator.
x/(3/8) * (3/8) = (64/3) * (3/8)
See that we have a 3 multiplying and another dividing, we can eliminate them.
x = 64/8
x = 8
So, if y decreases to 3/8 x will decrease to 8. Notice that y is decreasing in a half as 3/8 is the half of 3/4, and x is also decreasing in a half from 16 to 8, what makes sense.