Directions: Study the table below carefully and answer the given question.

The table displays the total number of laptops sold by five different stores (P, Q, R, S, and T), which sell two brands of laptops (Dell and HP), along with the ratio of Dell laptops sold to HP laptops sold by each store.

Stores	Total number of Laptops (Dell and HP)	Ratio of Dell Laptops : HP Laptops
P	400	$2:3$
Q	550	$6:5$
R	700	$3:4$
S	600	$8:7$
T	250	$11:14$

What is the ratio of the combined number of Dell laptops sold by stores P and S to the total number of Dell laptops sold by store R?

The correct answer is 8 : 5.

Step 1: Find the number of Dell laptops sold by Store P.
Total laptops sold by Store P = 400
Ratio of Dell laptops to HP laptops = 2 : 3
Sum of ratio terms = 2 + 3 = 5

Number of Dell laptops (Store P) = $\frac{2}{5}\times 400=160$

Step 2: Find the number of Dell laptops sold by Store S.
Total laptops sold by Store S = 600
Ratio of Dell laptops to HP laptops = 8 : 7
Sum of ratio terms = 8 + 7 = 15

Number of Dell laptops (Store S) = $\frac{8}{15}\times 600=320$

Step 3: Calculate the combined number of Dell laptops sold by stores P and S.

Combined Dell laptops (P + S) = $160+320=480$

Step 4: Find the number of Dell laptops sold by Store R.
Total laptops sold by Store R = 700
Ratio of Dell laptops to HP laptops = 3 : 4
Sum of ratio terms = 3 + 4 = 7

Number of Dell laptops (Store R) = $\frac{3}{7}\times 700=300$

Step 5: Calculate the required ratio.
Ratio = Combined Dell laptops (P and S) : Dell laptops (Store R)
Ratio = 480 : 300

Simplifying the ratio by dividing both sides by 60:

$\frac{480}{60}:\frac{300}{60}=8:5$

Thus, the required ratio is 8 : 5.