It is: 100% increase
+200%
To find the date 18 months before January 9, 2019, subtract 18 months from that date. Starting from January 9, 2019, going back 12 months takes you to January 9, 2018, and an additional 6 months back lands you on July 9, 2017. Therefore, 18 months before January 9, 2019, is July 9, 2017.
The rate of change, with respect to x, is -21.
9-18 months
% rate:= 9/50 * 100%= 0.18 * 100%= 18%
The rate is 1 battery for 2 dollars.
1168.21
15 and 6 months
Around 9-18 months old.
9 Month and 18 Days
18% = 18/100 = 9/50
9/1 X 2 = 18/2