Answer: Tom saves $21
Step-by-step explanation: The monthly earning has been given as $30. The spendings are expressed as fractions of the total earnings. The expenses are as follows;
Lunch = one tenth of the earnings
Lunch = 1/10 x 30
Lunch = 30/10
Lunch = 3
Also he spends the following on music
Music = one fifth of the earnings
Music = 1/5 x 30
Music = 30/5
Music = 6
So he spends a total of 3 plus 6 which equals 9 dollars out of his earnings. His savings becomes
Savings = 30 - 9
Savings = 21
Therefore his savings is $21