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How many kilograms of a 5% salt solution and how many kilograms of a 15% salt solution must be mixed together to make 45kg of an 8% salt solution?

Charlie tosses five coins.what is the probability that all five coins will land tails up.

Were only 64 seats. the remaining 6 students had to travel in a separate van. the equation 2b + 6 = 70 represents the given scenario. what does b represent? the number of buses the number of vans the number of students who rode on each bus the total number of students going to the football game