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3 votes
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Please help. I know it’s not the hardest, but I think I did something wrong when I solved it. Please include your work. Tysm! Please solve only number 27!

Please help. I know it’s not the hardest, but I think I did something wrong when I-example-1
User James Woodall
by
2.3k points

2 Answers

9 votes
9 votes

Answer:

4.2 (to 1d.p.)

Explanation:


(n+0.3)/(n-3.2\\)=9/2 9/2 = 4.5

Multiply both sides by (n-3.2)

n+0.3 = 4.5(n-3.2)

Now expand the brackets

n+0.3 = 4.5n - 14.625n

Now rearrange to make n the subject

n + 0.3 = 4.5n -14.625

-n -n

4.5n - n -14.625 = 0.3

3.5n -14.625 = 0.3

+14.625 +14.625

3.5n = 14.925

÷3.5 ÷3.5

n = 4.2

User Ashrith
by
3.1k points
8 votes
8 votes

1 Multiply both sides by

n

3.2

n−3.2.

n

+

0.3

=

9

2

(

n

3.2

)

n+0.3=

2

9

(n−3.2)

2 Simplify

9

2

(

n

3.2

)

2

9

(n−3.2) to

9

(

n

3.2

)

2

2

9(n−3.2)

.

n

+

0.3

=

9

(

n

3.2

)

2

n+0.3=

2

9(n−3.2)

3 Multiply both sides by

2

2.

2

n

+

0.6

=

9

(

n

3.2

)

2n+0.6=9(n−3.2)

4 Expand.

2

n

+

0.6

=

9

n

28.8

2n+0.6=9n−28.8

5 Subtract

2

n

2n from both sides.

0.6

=

9

n

28.8

2

n

0.6=9n−28.8−2n

6 Simplify

9

n

28.8

2

n

9n−28.8−2n to

7

n

28.8

7n−28.8.

0.6

=

7

n

28.8

0.6=7n−28.8

7 Add

28.8

28.8 to both sides.

0.6

+

28.8

=

7

n

0.6+28.8=7n

8 Simplify

0.6

+

28.8

0.6+28.8 to

29.4

29.4.

29.4

=

7

n

29.4=7n

9 Divide both sides by

7

7.

29.4

7

=

n

7

29.4

=n

10 Simplify

29.4

7

7

29.4

to

4.2

4.2.

4.2

=

n

4.2=n

11 Switch sides.

n

=

4.2

n=4.2

User Graeme Frost
by
3.2k points