In one day, annie traveled 7 times the sum of the number of hours brian traveled and 4. together they traveled 56 hours. find the number of hours each person traveled.

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What is 32+4 x (16 x 1/2) -2 show your work}

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.