The problem is 62-30=?

the example gives this problem -

33 - 16 = ?
+4
33 - 20 = 13
+4
33 - 16 = 17

so my question is how to do the 1st problem and in the example, how did they come up with 4 or why did they use 4 in the equation?

Abank gives 6.5% interest per year. what is the growth factor b in this situation?

The school that imani goes to is selling tickets to the annual dance competition. on the first day of the ticket sales the school sold 7 adult tickets and 5 child tickets for a total of $96. the school took in $40 on the second day by seling 3 adult tickets . find the price of an adult ticket and the price of a child ticket. solve by using substitution elimination college prep algebra math heres the 2 equations i came up with 7x+5y=96 and 3x+2y= -40 show all workiv be stuck on this.

Aplot of land has been surveyed for a new housing development with borders ab, bc, dc, and da. the plot of land is a right trapezoid with a height of 60 feet and an opposite leg length of 65 feet