9. Carlos is saving money to buy a set of golf clubs that cost [tex]$\$[/tex]530[tex]$. He already has $[/tex]\[tex]$80.00$[/tex] saved and can earn the rest of the money by mowing 15 lawns. If [tex]$m$[/tex] represents how much he earns for mowing each lawn, which of the following equations can be solved to find how much Carlos is paid for mowing each lawn?

(A) [tex]$530 = 15m + 80$[/tex]

(B) [tex]$530 = 15m - 80$[/tex]

(C) [tex]$530 - m = 80$[/tex]

(D) [tex]$530 + 80 = 15m$[/tex]



Answer :

To determine which equation correctly finds how much Carlos earns per lawn, let's break down the problem step-by-step.

Carlos needs to save \[tex]$530 to buy a set of golf clubs. He already has \$[/tex]80 saved and can earn the remaining money by mowing 15 lawns. We need to find the amount, [tex]\(m\)[/tex], he earns per lawn.

First, let's calculate how much more money Carlos needs to save to reach his goal of \[tex]$530: Amount still needed = Total cost - Amount already saved Amount still needed = \$[/tex]530 - \[tex]$80 Amount still needed = \$[/tex]450

Carlos earns money by mowing lawns. If he mows 15 lawns, the amount he needs to earn from each lawn mowed (denoted as [tex]\(m\)[/tex]) can be found by dividing the remaining amount needed by the number of lawns:

[tex]\(m\)[/tex] = Amount still needed / Number of lawns
[tex]\(m\)[/tex] = \[tex]$450 / 15 \(m\) = \$[/tex]30 per lawn

Next, we need to find the equation that correctly represents this situation.

Starting with option (A):
[tex]\(530 = 15m + 80\)[/tex]

If we insert the number we found, we need to verify that the equation balances:
[tex]\(530 = 15 \cdot 30 + 80\)[/tex]
[tex]\(530 = 450 + 80\)[/tex]
[tex]\(530 = 530\)[/tex] (True)

The equation is verified and balances correctly.

Now let's quickly examine the other options to show why they are incorrect:

(B)
[tex]\(530 = 15m - 80\)[/tex]
If we insert [tex]\(m = \$30\)[/tex]:
[tex]\(530 = 15 \cdot 30 - 80\)[/tex]
[tex]\(530 = 450 - 80\)[/tex]
[tex]\(530 = 370\)[/tex] (False)

(C)
[tex]\(530 - m = 80\)[/tex]
If we insert [tex]\(m = \$30\)[/tex]:
[tex]\(530 - 30 = 80\)[/tex]
[tex]\(500 = 80\)[/tex] (False)

(D)
[tex]\(530 + 80 = 15m\)[/tex]
If we insert [tex]\(m = \$30\)[/tex]:
[tex]\(530 + 80 = 15 \cdot 30\)[/tex]
[tex]\(610 = 450\)[/tex] (False)

Only option (A) verifies correctly:
[tex]\(530 = 15m + 80\)[/tex]

Therefore, the correct equation that can be solved to find how much Carlos is paid for mowing each lawn is:

(A) [tex]\(530 = 15m + 80\)[/tex]