Question

On a certain map, a distance of 40 miles is represented by 1cm. How many miles are represented by 2.2cm on the map ?

Answer 1

okay so we know that 2 cm is 80 miles, now we just need to find what the .2 on the map is

Answer 2

Should I multiply ?

Answer 3

okay, so if I recall, you should find 20% of 40 and add 80 to that, since the .2 in 2.2 is really 0.20 which is equal to 20%

Answer 4

so add 80+8 I think

Answer 5

Which is 160

Answer 6

no

Answer 7

80+8=88

Answer 8

I mean 88

Answer 9

right

Answer 10

Sorry I'm not so focused

Answer 11

I am not really sure if the .2 in 2.2 stands for a .02 or a .20

Answer 12

but I think this is the answer: 88

Answer 13

@OregonDuck

Answer 14

Since a map scale is a ratio, map scale problems can usually be solved by a proportion.

Answer 15

You are given a real distance and a map distance:

Real distance Map distance
40 miles 1 cm

This allows you to establish a ratio, which is the scale of the map:

40 miles : 1 cm

Answer 16

Now you are given a map distance and an unknown real distance

We can let x represent the unknown real distance.

Real distance Map distance
x 2.2 cm

This can be written as a ratio:

x : 2.2 cm

Answer 17

The map scale ratio equals the ratio with the unknown real distance, so we write an equation showing the ratios are equal. An equation that is two equal ratios is called a proportion. Also, there are several ways of writing a ration.
The ratio of x to y can be written in these ways:
x to y
x : y
x/y

Let's write an equation with our ratios, but at the same time let's change the ratios to the fraction form:

\(\large \dfrac{40~miles}{1~cm} = \dfrac{x}{2.2~cm} \)

Answer 18

Should I multiply 40 by 2.2 ?

Answer 19

Now we need to solve the proportion for x.

We cross multiply:

\(1 \times x = 40 \times 2.2\)

Now we simplify:

\(x = 88\)

Answer: the distance is 88 miles

Answer 20

I understand it so much better now thank you so much I really appreciated that @mathstudent55 and @heretohelpalways :)

Answer 21

I am glad to read/hear that. Happy Openstudying! :)

Answer 22

You are very welcome.
I'm glad you understand it better now.