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2 years ago

How many different 2-digit numbers are there with the following property:the tenth digit is greater than the units digit?

Mathematics

1 answer:

Serggg [28]2 years ago

7 0

Answer:

Step-by-step explanation:

Simply start by listing out the numbers from smallest to largest.

We start out with the smallest number following this information being the number 10. The next are 21 and 20. The next are 32, 31, and 30. We can start to see a pattern. If the ten's digit is n, then there are n numbers within that ten-group that have a greater 10's digit than unit's digit. The largest ten-group (90 to 98) has 9 integers following the rules established. Thus, the number of 2-digit integers that have ten's digits greater than units digit is 1+2+3+...+9=45

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Sixteen plus five times a number is more than the number plus 32. Write an inequality and solve it.

Margarita [4]

Answer:

x>4

Step-by-step explanation:

16+5x>x+32

5x>x+16

4x>16

x>4

4 0

3 years ago

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Question 9 unsaved the starting salaries of individuals with an mba degree are normally distributed with a mean of $54,000 and a

ra1l [238]

Unsaved?

Anyway, 60,000 is one standard deviation above the mean. By the 68-95-99.7 rule 68% of the probability is between -1 and +1 standard deviations, so 34% between 0 and 1 sigma so 50%-34%=16% above one sigma.

Answer: 16%

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3 years ago

A country's population in 1992 was 72 million. In 1998 it was 76 million. Estimate the population in 2012 using the exponential

stepan [7]

We assume the annual percentage increase is the same. We will work out the constant k using the formula

We have
P = 76
A = 72
t = 6 years (from 1992 to 1998)

Substitute into the formula
$76=72e^{6k}$
$\frac{76}{72}=e^{8k}$
Take log both sides give
$ln( \frac{76}{72})=ln(e^{6k})$
$0.05406722127=6k$
$k=0.009$

We can now work out the number of population by the end of 2012 using the formula

We have
A = 72 million
k = 0.009
t = 10 years (1992 to 2012)

$P=72e^{0.009*10}$ $P=78.78$ ≈79 million

7 0

3 years ago

The train station clock runs too fast and gains 7 minutes every 4 days. How many minutes and seconds will it have gained at the

Olegator [25]

16 minutes and 15 seconds.

4x2=8 8 days = 14 minutes
7/4=1.75= 2 minutes 15 seconds= total of 16min 15sec

3 0

3 years ago

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Can someone help with this challenging graph

-BARSIC- [3]

Answer:

(a) (-∞, -8) (-6, -4) (-2, ∞)

(b) -6, -2

(d) 5

Step-by-step explanation:

(a) A function is "decreasing" when the y-value decreases as the x-value increases.

⇒ the function is decreasing over these intervals : (-∞, -8) (-6, -4) (-2, ∞)

(b) Local maxima are the points on the function where it reaches a maximum.

⇒ maxima at x = -6 and x = -2

(d) 5

5 0

2 years ago