Verified answer

Hello,

Just read it slowly and carefully:

"mario’s age" → 𝑀

"8 years ago, mario’s age" → 𝑀−8

"the age he will be in 11 years" → 𝑀+11

"half of the age he will be in 11 years" → (𝑀+11)/2

Thus:

"8 years ago, mario’s age was half of the age he will be in 11 years"

→ 𝑀−8=(𝑀+11)/2

So, we have to solve:

𝑀 − 8 = (𝑀 + 11)/2

2𝑀 − 16 = 𝑀 + 11

𝑀 = 27

Mario is 27. ◄◄◄ANSWER

Check:

Eight year ago, Mario was 19.

In eleven years, he'll be 38.

And indeed, 19 is half of 38.

QED.

Regards,

Dragon.Jade :-)

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Let present age be x

Age eight years ago was x - 8 years

Age in 11 years will be x + 11 years

x - 8 = (1/2) ( x + 11 )

2x - 16 = x + 11

x = 27

Mario is 27 years old

2(m - 8) = m + 11

2m - 16 = m + 11

m = 25

x = age 8 years ago

x = (x+11)/2

2x = x + 11

x = 11

now he is 11+8 = 19