Grace starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 14 each week for a number of weeks, w. she writes the expression 100(14)w to find the amount of radioactive substance remaining after w weeks.

ryan starts with 1 milligram of a radioactive substance. the amount of the substance decreases by 40% each week for a number of weeks, w. he writes the expression (1 – 0.4)w to find the amount of radioactive substance remaining after w weeks.

use the drop-down menus to explain what each part of grace’s and ryan’s expressions mean.

a complex number is a number that can be expressed in the form a + bi, where a and b are real numbers, and i is a solution of the equation x2 = −1. because no real number satisfies this equation, i is called an imaginary number. has no real solution, since the square of a real number cannot be negative.

the answer is mp

step-by-step explanation:

5/20 so 25%

step-by-step explanation:

0 and 5 minutes

step-by-step explanation:

given that one morning eight buses arrive late by the number of minutes given below:

0 8 2 6 9 2 0 7 8

write these in ascending order

0   0 2 6 7 8 8 9

in the afternoon two more buses arrive at the bus stop say by x and y minutes late.

total number of buses = 10

median = average of 4th and 5th after arranging in ascending order

since 4th entry is 6, the values of x and y should be below 6

also given 0 is the mode so either x or y or both should be 0 because then only 0 gets the maximum frequency and hence mode

thus we have

0 0 0 2 6 7 8 8 9 and another unknown entry which is below 6.

since median is 3.5, we have the unknown entry to be 5 only because then only median =( 2+5)/2

thus the after noon buses were late by 0 and 5 minutes.