Christo and Aris had 207 marbles. Christo bought another 12 marbles and Aris gave his brother 12 marbles. As a result, Christo had 1/2 as many marbles as Aris. How many marbles did Aris have at first?

Guest Oct 3, 2021

#1**+2 **

c+ a = 207 or c = 207-a

c+12 = 1/2 (a-12) sub in the red equation

207-a + 12 = 1/2 a - 6

225 = 1 1/2 a

a = 150

ElectricPavlov Oct 4, 2021