Answer:
1.235 kg
Explanation:
Let's assume that each packet of flour and salt weighs the same.
When we remove 7 packets of flour, we are left with 5 packets of flour and 8 packets of salt. The total number of packets is 13 and their total mass is 9.9 kg.
Therefore, the average mass of each packet is 9.9 kg ÷ 13 = 0.76 kg.
Since we know that 12 packets of flour and 8 packets of salt have a total mass of 19 kg, we can subtract the mass of the 12 packets of flour (12 × 0.76 kg = 9.12 kg) from the total mass to find the mass of the 8 packets of salt:
19 kg - 9.12 kg = 9.88 kg
Finally, we can divide the mass of the 8 packets of salt by the number of packets to find the mass of each packet:
9.88 kg ÷ 8 = 1.235 kg
Therefore, each packet of salt weighs approximately 1.235 kg.