Answer:
127.2 litres
Step-by-step explanation:
Let x be the number of 80% strawberry juice( in litres ) mixed with 6 litre of 20% strawberry juice mixture to obtain 55% strawberry juice,
∵ Resultant mixture = (6+x) litres,
Since, strawberry in x litres + strawberry in 6 litres = strawberry in resultant mixture
⇒ 80% of x + 20% of 6 = 55% of (60+x)
⇒ 80x + 20 × 6 = 55(60+x)
⇒ 80x + 120 = 55 × 60 + 55x
⇒ 80x = 3300 + 55x - 120
⇒ 80x - 55x = 3180
⇒ 25x = 3180
⇒ x = = 127.2
Hence, 127.2 litres of 80% mixture should be mixed.