Marcela is registering for her college classes, which cost $105 per unit. how many units can she take to have a maximum cost of $1,365?

Marcela can take up to 13 units.  

Step-by-step explanation:

In order to find the number of units that Marcela can take for her college classes, we can set up an inequality and solve for the variable.  Since each unit costs $105, we can say that 105u ≤ 1365 where u = the number of units.  The number of units multiplied by the cost per unit, must be less than or equal to $1,365.  In order to solve for 'u', we can use inverse (opposite) operations and get rid of the coefficient by dividing both sides of the inequality by 105.  1365÷105 = 13.  So, the number of units that Marcela can take must be less than or equal to 13 units.  

Marcela can use 13 units.

step-by-step explanation:

51

step-by-step explanation:

73-22=51 the   mass number minus the amount of protons gives you the amount of neutrons