Question

Un turist a cheltuit o suma de bani in trei zile astfel:in prima zi a cheltuit 20 % din suma si inca 120 de lei, a doua zi 40% din rest si inca 200 lei, iar a treia zi 50 % din rest si inca 150 de lei, ramanandu-i necheltuiti 350 de lei. Care a fost suma initiala?
Va rog ajutati-ma repede e urgent!!Dau Coroana!!

Answer 1

x=suma initiala
20%x+120=x/5+120=ziua 1
x-x/5-120=4x/5-120=rest
(4x/5-120) × 40%+200=(4x/5-120) × 2/5+200 =8x/25-48+200= =8x/25+152=ziua 2
4x/5-120-8x/25-152=12x/25-272=rest
(12x/25-272) × 50%+150=(12x/25-272) × 1/2+150= 12x/50-136+150=
=12x/50+14 =6x/25+14=ziua 3
x/5+120+8x/25+152+6x/25+14+350=x
x/5+14x/25+636=x
5x+14x+15900=25x
6x=15900
x=2650 lei