Question

How many integers between 100 and 999, inclusive, have all their digits odd and distinct?

261

likes
1304 views

Answer to a math question How many integers between 100 and 999, inclusive, have all their digits odd and distinct?

Expert avatar
Neal
4.5
95 Answers
Para encontrar o número de inteiros entre 100 e 999 (inclusive) onde todos os dígitos são ímpares e distintos, precisamos considerar as combinações possíveis. 1. O algarismo das centenas pode ser qualquer algarismo ímpar de 1 a 9 (1, 3, 5, 7 ou 9). 2. O algarismo das dezenas pode ser qualquer algarismo ímpar, exceto aquele já escolhido para o algarismo das centenas. 3. O algarismo das unidades pode ser qualquer algarismo ímpar, exceto os já escolhidos para os algarismos das centenas e das dezenas. Portanto, o número de inteiros que atendem a essas condições é o produto do número de escolhas para cada dígito: 1. Existem 5 opções para o algarismo das centenas (1, 3, 5, 7, 9). 2. Existem 4 opções para o algarismo das dezenas (excluindo a já escolhida para o algarismo das centenas). 3. Existem 3 opções para o algarismo das unidades (excluindo as já escolhidas para os algarismos das centenas e dezenas). Portanto, o número total de inteiros que atendem às condições é: \[ 5 \vezes 4 \vezes 3 = 60 \] Portanto, existem 60 números inteiros entre 100 e 999 (inclusive) onde todos os dígitos são ímpares e distintos.

Frequently asked questions (FAQs)
What is the value of sine function at an angle of 45 degrees?
+
How many ways can 5 students be seated in a row of 8 chairs?
+
What is the domain of the logarithmic function f(x) = log(x)/ln(x)?
+
New questions in Mathematics
Find an arc length parameterization of the curve that has the same orientation as the given curve and for which the reference point corresponds to t=0. Use an arc length s as a parameter. r(t) = 3(e^t) cos (t)i + 3(e^t)sin(t)j; 0<=t<=(3.14/2)
12-6x=4x+2
Karina has a plot of 5,000 square meters in which she has decided that 60% of it will be used to plant vegetables. Of this part, 12% will be dedicated to planting lettuce. How much surface area of the plot will be used for cultivation?
How many percent is one second out a 24 hour?
In a random sample of 600 families in the Metropolitan Region that have cable television service, it is found that 460 are subscribed to the Soccer Channel (CDF). How large a sample is required to be if we want to be 95% confident that the estimate of “p” is within 0.03?
Determine the correct value: A company knows that invoices pending collection have a normal distribution with a mean of $1.65 million, with a standard deviation of $0.2 million, then: The probability that an invoice pending collection has an amount that is within more than 2 deviations below the mean, is:
What payment 7 months from now would be equivalent in value to a $3,300 payment due 23 months from now? The value of money is 2.7% simple interest. Round your answer to 2 decimal places. Show all work and how you arrive at the answer..
I need .23 turned into a fraction
B - (-4)=10
4X^2 25
The expected market return is 13,86% and the risk free rate 1%. What would then be the risk premium on the common stocks of a company which beta is 1,55? (in %, 2 decimal places)
Perpetual annuities are a series of payments whose duration has no end. Explain how can we calculate them, if they have no end?
The ninth term of a given geometric progression, with reason q , is 1792, and its fourth term is 56. Thus, calculate the fourth term of another geometric progression, whose ratio is q +1 and whose first term is equal to the first term of the first P.G. described.
Your boss asks you to plan the sample size for a randomized, double-blind, controlled trial in the clinical development of a cure for irritable bowl disease. Current standard treatment shall be compared with a new treatment in this trial. The S3-guideline of AWM demonstrated a mean change of the summary score of the validated health related quality of life questionnaire at 8 weeks of 16 with standard deviation 23 under standard treatment. You quote the drop-out rate of 11% from literature (previous phase of clinical development). Your research yielded a clinically important effect of 4 that has been found to be the Minimal Clinically Important Difference (MCID). In order to demonstrate superiority of the new treatment over standard of care, you assume that the change in of the summary score of the validated health related quality of life questionnaire follows a normal distribution, and that the standard deviation is the same for both treatments. How many patientes would one need to recruit for the trial to demonstrate the clinically interesting difference between treatments at significance level 5% with 95% power?
I. Order to add 40.25+1.31+.45 what is the first action to do ?
Engineers want to design seats in commercial aircraft so that they are wide enough to fit ​95% of all males.​ (Accommodating 100% of males would require very wide seats that would be much too​ expensive.) Men have hip breadths that are normally distributed with a mean of 14.4 in. and a standard deviation of 1.2 in. Find P95. That​ is, find the hip breadth for men that separates the smallest ​95% from the largest 5​%.
For what values of m is point P (m, 1 - 2m) in the 2⁰ quadrant?
factor the polynomial completely over the set of complex numbers b(x)=x^4-2x^3-17x^2+4x+30
simplify w+[6+(-5)]
Sin(5pi/3)