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2 years ago

An arithmetic progression has first term 11 and Fourth term 32. Fine the sum of the first nine term

Mathematics

2 answers:

bonufazy [111]2 years ago

6 0

Answer:351

Step-by-step explanation:Try to plus the same number every time, I used 7 and it worked. : )

schepotkina [342]2 years ago

4 0

Let the first term be a, 4th term be $a_{4}$ , difference between terms be d, and sum of first nine terms be $S_{9}$ .

$a_{4}$ = a + 3d

32 = 11 + 3d

3d = 32 - 11

3d = 21

d = 7

$S_{9}$ = $\frac{9}{2} (2a + (9-1)d)$

= $\frac{9}{2} (22+56)$

= 9(11+28)

= 9(39)

= 325

Sum of first nine terms is 351.

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Eugene walked all the way to school at 3 mph then realized she forgot her math book (how could she?!), so she ran back at 7 mph.

Fynjy0 [20]

$\text{Answer: }1\frac{23}{40}\ miles\text{ far she live from school.}$

Explanation:

Since we have given that

Speed at which Eugene walked all the way to school = 3 mph

After realizing that she forgot her math book, she ran back

Speed at which Eugene walked back to her house = 7 mph

Let the distance between her house and her school be x

According to question,

$\frac{x}{3}+\frac{x}{7}=\frac{45}{60}\\\\\frac{7x+3x}{21}=\frac{3}{4}\\\\\frac{10x}{21}=\frac{3}{4}\\\\x=\frac{3\times 63}{4\times 10}=\frac{63}{40}=1\frac{23}{40}\ miles.$

Hence,

$1\frac{23}{40}\ miles\text{ far she live from school.}$

8 0

2 years ago

-5y + 8 = 3y + 10. Calculate and show work

maksim [4K]

2x+3=[email protected]x=6(2)(6)+3=1515=15

4 0

3 years ago

Read 2 more answers

-28 = -7(3x + 4) +21x

Vlada [557]

Answer:

1 Expandir.

-28=-21x-28+21x

−28=−21x−28+21x

2 Simplifica -21x-28+21x−21x−28+21x a -28−28.

-28=-28

−28=−28

3 Ya que ambos lados son iguales, hay infinitas soluciones.

Soluciones Infinitas

Step-by-step explanation:

7 0

2 years ago

At Friday's football game, 1,294 tickets were sold for a total amount of $8,816.00. If each student ticket costs $5.00, and each

NeTakaya

Answer:

512 student tickets.

Step-by-step explanation:

Let x be number of student tickets and y be number of adult tickets.

We have been given that at Friday's football game 1,294 tickets were sold. We can represent this information as:

$x+y=1294...(1)$

We are also told that each student ticket costs $5.00, and each adult ticket costs $8.00 and 1,294 tickets were sold for a total amount of $8,816. We can represent this information as:

$5x+8y=8,816...(2)$