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Learn Java: Manipulating Variables
Addition and Subtraction

In our bank account example from the last exercise, we used + to add!

double balance = 20000.99; double depositAmount = 1000.0; double updatedBalance = balance + depositAmount; //updatedBalance now holds 21000.99

If we wanted to withdraw from the balance, we would use -:

double withdrawAmount = 500; double updatedBalance = balance - withdrawAmount; //updatedBalance now holds 19500.99

Addition and subtraction work with ints as well!

int numPicturesOfCats = 60 + 24;

If you had 60 pictures of cats on your phone, and you took 24 more, you could use the above line of code to store 84 in numPicturesOfCats.



Create an int variable called animalsInZoo that holds the amount of zebras plus the amount of giraffes at the zoo.

Then, print your animalsInZoo variable.


Two of the zebras have been traded to a neighboring rival zoo. Subtract 2 from the number of zebras and store the result in a variable called numZebrasAfterTrade.

Then, print the numZebrasAfterTrade variable!

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