A quantity with an initial value of 920 decays exponentially at a rate of 85% every week. What is the value of the quantity after 21 days, to the nearest hundredth?

920 * .85 = 782       One week

782 * .85 = 664.70  Two weeks

664.70 * .85 = 564.995 Three weeks

Step-by-step explanation:

7. 153.86 ft

8. 12.56 ft

9. 78.5 m

10. 379.94 in

11. 132.665 m

12. 12.56 yd

13. 226.865 ft

14. 113.04 ft

15. 63.585 ft

16. 254.34 m

17. 50.24 cm

step-by-step explanation:

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38.5

step-by-step explanation:

lets say, first number = r

second number = 3r+7

total = 49

(r)+(3r+7)= 49

4r+7 = 49

4r = 42

r = 42/4

r= 10.5

3r+7 = 3(10.5)+7 = 38.5

hope this