Multiplying fractions by whole numbers:
1. You have to convert the whole number into an improper fraction.
2. You then multiply the fractions straight across.
Ex: 2/3 × 6 =2/3 × 6/1 = 2×6/3×1= 12/3= 4
Elga's age = x
Alvin's age = x + 7
x + x + 7 = 97.
Simplify the left side of the equation
2x + 7 = 97.
Subtract 7 from each side
2x = 90.
Divide each side by 2
x = 45
Since x is equal to Elga's age, Elga is 45 years old
What is the mean, median and mode for...45,50,55,55,55,60,60,60,65,65,70?
Alexxx [7]
Answer:
Mean = 58.18
Median = 60
Modes = 55 and 60
Step-by-step explanation:
To find the mean/average, add up all the numbers and divide the sum by the # of numbers there are (ex. there are 11 numbers so divide the sum by 11).
The median is the middle number of a set. In this case, the middle number is easy to see because the # of numbers is odd, but if it was even, just find the average of the two middle numbers.
The mode is/are the most frequent number(s) in the set. In this set, the numbers that appear the most are 55 and 60.
The probability is 0.8997.
We will use a z-score to answer this question. z-scores are given by the formula

With our information, we have

Looking this up in a z-table (http://www.z-table.com) we see that the area to the left of this (everything less than, up to this value) is 0.8997.