Question

↔ Try this Guys ☺

☑ No Spams Allowed ❌

Answer 1

12(0.8-x)+13x+15*0.2=13

solving of x,
9.6-12x+13x = 10
x = 0.4

40% of 13x isotope in abudance

Answer 2

Answer:

$.y3 { \sqrt[ \frac{ { \sqrt[ \sqrt{y \times \frac{?}{?} } \times \frac{?}{?} \times \frac{?}{?} ]{?} }^{?} }{?} ]{?} }^{2}$