A computer is on sale for Rs 1,600, which is a 20% discount off the regular price
What is the regular price?

y x 0.8 = 80% of y, so do it in reverse. In this case, y = 1600, so 1600/0.8 = 2000

Edit: Keep in mind 1600 is 80% of Regular Price

Rs. 1920

Step-by-step explanation:

Rs 1600: 20% discounted price

1600+ [ (20÷100) x 1600]

1600+ 320

= Rs. 1920 (Regular price)

We need to finish writing out the problem using what we know about the distance both planes traveled.

Plane 1 - 1050 miles - 300 mph - ? time

Plane 2 - 1050 miles - same time as Plane 1 less 1.75 hours.

Let's fill in the gaps.

Plane 1 - ? time 1050/300 = 3.5 hours

Plane 2 - ? time Take 3.5 hours and subtract 1.75 = 1.75 hours

Now we figure the speed of plane 2

1050/1.75 = 600 miles an hour

Another quick way was to note that 1.75 was half of 3.5 hours so the speed was 2x as fast!