learn-co-curriculum/hs-variables-mini-lab

##Mini-Lab: Variables Practice

###What is a Variable?

We use variables in programming to store pieces of data. Variables can store any type of data (strings, integers, floats, etc). When we name a variable, we use all lowercase letters. For example:

dog = "Fido"

In this example, all we've done is defined a variable named dog and set it equal to the string Fido. Now, any time we tell our program to puts dog, it will print out Fido.

puts dog
puts dog
puts dog

In this example, we should see Fido printed out three times.

What would happen if we did the following:

name = "Fido"
name = "Bessie"

puts name

On the first line, we assigned the variable name to store Fido. On the next line, we reassigned the value of the variable name to store Bessie. Each variable can only store one value, so all we did was overwrite the value of the name variable. When we puts name on the last line, we will see Bessie printed out.

What if we want to have more than one word in our variable? Like:

best friend = "Steph"

puts best friend

Ruby gives us an error! undefined method 'best'. Ruby doesn't know what best is because of the space between the words best and friend. Ruby doesn't recognize best as a key word (like puts) or as a data type, so it throws an error. It's just like when we're creating directories or files in the terminal, the space confuses the computer. Instead, replace spaces with underscores:

best_friend = "Steph"

puts best_friend

###Let's practice!

What will be printed to the screen after running each of these? Talk to a partner and decide on an answer before running your code from a Ruby file that you create called variables_practice.rb.

???

Variables Practice

?: What is the outcome of running the code below?

a = 25
b = 36

puts a * b

( ) 61 (X) 900 ( ) 2536

?: What is the outcome of running the code below?

dog = "Ralph"
cat = "Whiskers"

puts dog + cat

(X) RalphWhiskers ( ) DogCat ( ) Ralph Whiskers

?: What is the outcome of running the code below?

band = "The Beatles"

puts "My favorite band is " + band 

( ) My favorite band isThe Beatles (X) My favorite band is The Beatles ( ) myfavoritebandisthebeatles

?: What is the outcome of running the code below?

first = "BARACK"
last = "OBAMA"
age = 53

puts "The president of the US is " + first.capitalize + " " + last.capitalize + " and he is " + age.to_s + " years old."

(X) The president of the US is Barack Obama and he is 53 years old. ( ) The president of the US is BARACK OBAMA and he is 53 years old. ( ) The president of the US is Barack Obama and he is fifty-three years old.

?: What is the outcome of running the code below?

artist_first = "NiCKi"
artist_last = "MiNaj"

puts "When I listen to " + artist_first.upcase + " " + artist_last.downcase + " I feel like my brain is melting."

( ) When I listen to NICKI MINAJ I feel like my brain is melting. ( ) When I listen to Nicki Minaj I feel like my brain is melting. (X) When I listen to NICKI minaj I feel like my brain is melting.

?: What is the outcome of running the code below?

name = "Bill"
age = 16
location = "New York"

puts "Hi. I'm " + name.upcase + ". I'm from " + location.swapcase + " and in ten years I'm going to be " + (age+10).to_s

(X) Hi. I'm BILL. I'm from nEW yORK and in ten years I'm going to be 26 ( ) Hi. I'm BILL. I'm from NEW YORK and in ten years I'm going to be 16 ( ) Hi. I'm Bill. I'm from New York and in ten years I'm going to be 26

?: What would be the difference between the product and the sum?

Set x equal to 34679, y equal to 566 and zequal to 47. Set a variable equal to the product of these three numbers. Then set a variable equal the sum of the three numbers. Find the difference between the product and the sum.

( ) 35,292 (X) 922,495,466 ( ) 922,466,495

???

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hs-variables-mini-lab's Issues

Add to_i, to_s, and to_f in as part of the challenge

Favorite band case wrong

The answer is wrong, should not be all lower case.