aig math(please answer)
posted by lidia on .
4 kg of apples and 1 kg of berries cost $5.75 altogether. 2 kg of apples and 1 kg of berries cost a total of $3.25.How much must i pay to buy 5 kg of apples and 5 kg of berries?please show work.
my answer is $10.50 am i right if not please tell me why and how?

Not quite, I think. Call the number of kilos of apples A, and the number of kilos of berries B. Then you know that:
4A + B = $5.75
2A + B = $3.25
so subtract the second equation from the first, and you'll get
2A = $2.50, so A = $1.25. Subtract the 2A = $2.50 from the second equation and you'll get
B = $0.75, so A + B = $2, which means that 5A + 5B = $10.