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BlackZzzverrR [31]
3 years ago
6

sana is senior to Mona by 18 years after 6 years.Sana will be twice as old as Mona. find Mona,s percentage​

Mathematics
1 answer:
Gwar [14]3 years ago
3 0
Let
Present age of Sana = s
Present age of Mona = m


Sana is senior to Mona by 18 years
s=m+18............(1)

After 6 years
Sana will be = s+6
Mona will be = m+6
Then
Sana will be twice as old as Mona
(s+6)=2(m+6)
s+6=2m+12
s=2m+12-6
s=2m+6.............(2)
Put the value of s from (2) to (1)
2m+6=m+18
2m-m=18-6
m=12
Put the value of m in (1)
s=m+18
s=12+18
s=30



Present age of Sana = s = 30 years old
Present age of Mona = m = 12 years old
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