Each two digit number has two numbers (duh!). Let's allow the tens digit to be x and the units digit to be y. Tens digit is 3 less than the units digit: x = y-3 Original number is 6 more than 4 times the sum of the digits: 10x+y-6 = 4x + 4y This gives us simultaneous equations!First let's clear the mess: 1. x= y-32. 6x-3y=6 Substitute 1 into 2: 6(y-3) -3y =66y - 18 - 3y = 6
3y = 24y = 8 Our units digit is 8 Substitute y= 8 into 1. x = y - 3x = 5 Our tens digit is 5 Therefore, our number is 58
Answer:
B) x + s = 90, x - s = 20
Step-by-step explanation:
x + s = 90 represents that both Xavier and Sara's money combined is $90.
x - s = 20 represents that Xavier has 20 more dollars than Sara.
Answer:
34%
Step-by-step explanation:
Given that the distribution of daily light bulb request replacement is approximately bell shaped with ;
Mean , μ = 45 ; standard deviation, σ = 3
Using the empirical formula where ;
68% of the distribution is within 1 standard deviation from the mean ;
95% of the distribution is within 2 standard deviation from the mean
Lightbulb replacement numbering between ;
42 and 45
Number of standard deviations from the mean /
Z = (x - μ) / σ
(x - μ) / σ < Z < (x - μ) / σ
(42 - 45) / 3 = -1
This lies between - 1 standard deviation a d the mean :
Hence, the approximate percentage is : 68% / 2 = 34%
Answer:14
Step-by-step explanation:
A nickel is 5 cents (20% of dollar)
and a quarter is 25 cents (25% of dollar)
We have given a pile of 42 coins worth of $4.90
Let x be the no nickels and
y be the no of quarter
therefore
x+y=42 -----1
+
=4.90 ---2
Solving
we get
x=14 & y=28
Therefore no of nickels is 14 & no of quarters is 28
Answer:
= 8
Step-by-step explanation:
Solve for x by simplifying both sides of the equation, then isolating the variable.
x = 8
Hope it helps!