We will call D1 and D2 the volume of dextrose at 2.5% and 30% respectively
D1 + D2 = 500 (1)
D1*2,5/100 + D2*30/100 = 500*10/100 (2)
(2,5D1+30D2)/100 = 50
2,5D1 +30D2 = 50*100 = 5.000 (2)
D1 = 500 - D2 Now we clear D1 in (1)
2,5(500-D2) + 30D2 = 5.000 and we substitute in (2)
1.250 - 2,5D2 + 30D2 = 5.000
27,5D2 = 5.000 - 1.250 = 3.750
D2 = 3.750/27,5 = 136ml +4/11ml
D1 = 500ml - 136ml +4/11ml
D1 = 363ml +7/11ml
ANSWER 363ml+7/11 ml of dextrose 2,5% and 136ml+4/11 ml dextrose 30%
[tex]\textbf{Spymore}[/tex]