Science

Math

Humanities

... and beyond

Socratic Meta
Featured Answers

Topics

Question #112a0

1 Answer

Mar 7, 2017

The Lopez sprinkler was used for $15$ $15$ hours.
The Flores sprinkler was used for $20$ $20$ hours.

Explanation:

Let
$XXX L$ $color(white)("XXX")L$ be the number of hours the Lopez sprinkler was used, and
$XXX F$ $color(white)("XXX")F$ be the number of hours the Flores sprinkler was used.

We are told:
[1] $XXX 40 L + 25 F = 1100$ $color(white)("XXX")40L+25F=1100$
[2] $XXX L + F = 35 XX \to XX L = 35 - F$ $color(white)("XXX")L+F=35color(white)("XX")rarrcolor(white)("XX")L=35-F$

[2] implies that
[3] $XXX 40 L = 1400 - 40 F$ $color(white)("XXX")40L=1400-40F$

Combining [3] with [1], we have
[4] $XXX 1400 - 40 F + 25 F = 1100$ $color(white)("XXX")1400-40F+25F=1100$

Simplifying
[5] $XXX - 15 F = - 300$ $color(white)("XXX")-15F=-300$
or
[6] $XXX F = 30$ $color(white)("XXX")F=30$

If $F = 20$ $F=20$ and $L = 35 - F$ $L=35-F$
$XXX L = 15$ $color(white)("XXX")L=15$

Related questions

See all questions in Linear, Exponential, and Quadratic Models

Impact of this question

1370 views around the world

You can reuse this answer
Creative Commons License