Question

Mihaela ,Alexandra si Costin au stans impreuna o suma de bani .Mihaela si Alexandra au impreuna suma de 324 lei.Alexandra si Costin au impreuna 362 lei, iar Mihaela si Costin au impreuna suma de 312 lei. Ce suma a pus fiecare?

Answer 1

m + a = 324

a + c = 362

m + c = 312

m + a + a + c = 324 + 362

m + 2 × a + c = 686

312 + 2 × a = 686

2 × a = 686 - 312

2 × a = 374

a = 374 : 2

a = 187

m = 324 - a

m = 324 - 187

m = 137

c = 362 - a

c = 362 - 187

c = 175