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WARRIOR [948]
3 years ago
12

selma is now 3 times older than joyce . four years ago , selma was 4 times as old as joyce was then . find their present ages

Mathematics
1 answer:
adoni [48]3 years ago
8 0

Present age of Selma = s

Present age of Joyce = j

Selma is now 3 times as old as joyce

s=3j........(1)

Four years ago,

s-4=j-4

then

Selma was 4 times as old as joyce

s-4=4(j-4)

s-4=4j-16

s=4j-16+4

s=4j-12.............(2)

Put the value of s in (2) from (1)

3j=4j-12

3j-4j=-12

-j=-12

Multiply by -1 both sides

j=12

Put the value of j in (1)

s=3j

s=3(12)

s=36

Present age of Selma = s = 36 years old

Present age of Joyce = j = 12 years old

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The school uses between 300 and 400 sheets of paper per school day. If paper costs the school $2.00 per 100 sheets, approximatel
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Answer:

  • Option A. $140.00

Explanation:

<u>1. Using the minimun number of sheets  of paper in the interval [300, 400]</u>

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c) Approimately 20 school days per month:

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7 0
3 years ago
Solve by unfolding: a0=2, and, n&gt;=1, a_n=7a_n-1.
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The nth term of this geometric series is a_n = 2(7)^(n-1).

Check:  What is the first term?  We expect it is 2.  2(7)^(1-1) = 2(1) = 2.  Correct.

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2 years ago
Factor the expression. Use the fundamental identities to simplify, if necessary.
Rasek [7]

Answer:

see explanation

Step-by-step explanation:

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Given

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