For this case we can define the following variable:
x: unknown number
We write the equation that models the problem:

From here, we clear the value of x.
We have then:

Answer:
Completing the sentence we have:
0.04 is 1/10 of 0.40
60 miles is equivalent to 2.4 inches.
Answer:
Teresa should build 7.5 inches model.
Step-by-step explanation:
Consider the provided information.
Teresa is building a scale model of the JP Morgan chase Tower in Houston.
Her scale model, 1.5 inches represents 61 meters.
The actual building is 305 meters tall,
First find how many 61's are there in 305.
For this divide 305 by 61.

Actual building is 5 times taller than 61. Thus the model should be 5 times taller than 1.5.
multiply 1.5 with 5 gives us:

Hence, Teresa should build 7.5 inches model.
Answer: Aproximately 2,525 balloons
Step-by-step explanation:
1. Find the volume of a balloon with the formula given in the problem, where
is the radius (
), then:

2. Convert the volume from m³ to lliters by multiplying it by 1,000:

3. You know that that 1 liter of helium can lift 1 gram and that Ryan weighs 5 stone and 5 pounds. So you must make the following conversions:
1 g=0.0022 lb
From 5 stones to pounds

4. Then Ryan's weigh is:
5lb+70lb=75lb
5. Then, if 1 liter of helium can lift 0.0022 lb, to lift 75 lb (which is the weight of Ryan) they need:

6. Then, to calculate the aproximated number of balloons they need to make him float (which can call
), you must divide the liters of helium needed to lift the weight of Ryan by the volume of a balloon, then the result is:

≈2,525 balloons.