3 years ago

I am not sure if this is right but some one help me

Mathematics

1 answer:

nadezda [96]3 years ago

5 0

Answer:

you are right

Step-by-step explanation:

You might be interested in

Given the sum s20= 910 of an arithmetic sequence and A20 = 95, Find A1

Inessa05 [86]

Step-by-step explanation:

Sn=n/2(2a+(n-1)d)

910=n/2{2a+(n-1)d}

1820=n{2a+(n-1)d}

1820=20{2a+(20-1)d}

1820=20{2a+19d}

91=2a+19d

An=a+(n-1)d

95=a+(20-1)d

95=a+19d

91=2a+19d

---------------

4=-a

a=-4

91=2a+19d

91=2(-4)+19d

91=-8+19d

91+8=19d

99=19d

d=99/19

A=-4

5 0

2 years ago

A swim meet has 13 contestants signed up for the 100-meter butterfly event. The first heat has 6 swimmers. How many different wa

tino4ka555 [31]

Answer:

6 swimmers in the first heat can be arranged in 1716 different ways.

Step-by-step explanation:

A swim meet has 13 contestants signed up. To calculate the arrangement of first 6 swimmers in first heat we will use combinations because order doesn't matter.

So to select 6 swimmers out of 13 contestants number of different ways

= $^{13}C_{6}$

= $\frac{13!}{(6!)(13-6)!}$

= $\frac{13\times 12\times 11\times 10\times 9\times 8\times 7!}{6!\times 7!}$

= $\frac{13\times 12\times 11\times 10\times 9\times 8}{6\times 5\times 4\times 3\times 2\times 1}$

= $\frac{1235520}{720}$

= 1716

Therefore, 6 swimmers in the first heat can be arranged in 1716 different ways.

5 0

3 years ago

2/5 of Janet's class prefers chocolate ice cream and 2/5 prefers vanilla ice cream. What part of the class prefers chocolate or

belka [17]

The answer is D, 4/5, because 2/5+2/5=4/5.

6 0

3 years ago

Read 2 more answers

b. You have saved $15,000 for a down payment. What is the max you can spend (max house price)? (4 points)

In-s [12.5K]

Answer:

maybe like 5k

Step-by-step explanation:

6 0

2 years ago

Take away 2 from 7 times h

yan [13]

Answer:7h-2

Step-by-step explanation:

take away 2 indicates -2

7 times h indicates 7h

then you have a few ways to write this out either: -2+7h or 7h-2

both are correct!

3 0

3 years ago