Answer:21
Step-by-step explanation:
10/(10+15)=14/(14+x)
10/25=14/(14+x)
Cross multiplying we get
10(14+x)=25x14
10(14+x)=350
Divide both sides by 10
10(14+x)/10=350/10
14+x=35
x=35-14
x=21
