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2 years ago

Which of these is a prime number 1,11,21,51 ?

Mathematics

2 answers:

kow [346]2 years ago

8 0

11,,21,51 are all prime numbers

avanturin [10]2 years ago

5 0

A prime number has exactly 2 different factors, 1 and itself.

11 is divisible only by 1 and 11.
11 is prime.

21 and 51 have a least three factors. They are not prime.
1 has only 1 factor. 1 is not prime.

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Solve for x. rs/x=1/4

Anit [1.1K]

Let's solve for x.rsx=14
Step 1: Multiply both sides by x.rs=14x
Step 2: Flip the equation.14x=rs
Step 3: Divide both sides by 1/4.14x14=rs14x=4rs
Answer:x=4rs

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3 years ago

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4a^2-8a=0solve by competing square

zalisa [80]

Answer:

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2 years ago

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If a+3b=13 and a+b=5 the value of b is

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Answer:b=4

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3 years ago

Write an equation for the nth term of the arithmetic sequence.

tresset_1 [31]

Answer:

Step-by-step explanation:

3, 9, 15, 21, ...

9-3 = 6; 15-9 = 6; 21-15 = 6 ⇒ d = 6

first term: a = 3

difference: d = 6

so the formula:

$a_n=a+d(n-1)\\\\a_n=69+6(n-1)\\\\a_n =3+6n-6\\\\\underline{a_n=6n-3}$

and:

$a_{50}=6\cdot50-3=300-3=297$

5 0

2 years ago

Ashley is packing her bags for her vacation. She has 8 unique Fabergé eggs, but only 5 fit in her bag. How many different groups

irakobra [83]

Answer:

56 groups of 5 Fabergé eggs can be taken.

Step-by-step explanation:

It is given that Ashley is packing her bags for her vacation. She has 8 unique Fabergé eggs, but only 5 fit in her bag. In order to find how many different groups of 5 Faberge' eggs can she take, we apply the combination formula:

$8C_{5}=\frac{8!}{5!(8-5)!}$

$8C_{5}=\frac{8!}{5!3!}$

$8C_{5}=\frac{8{\times}7{\times}6{\times}5!}{5!{\times}3{\times}2}$

$8C_{5}=56$

Thus, 56 groups of 5 Fabergé eggs can be taken.

8 0

3 years ago