. A retailer sold 10 packs of pens in 3 days. There were 48 pens in each pack. He sold twice as many pens on Sunday than on Monday. He sold 55 pens fewer on Tuesday than on Sunday. How many pens did the retailer sell on Monday?

The number of pens sold on Monday is 107 pens

Step-by-step explanation:

total pack of pen sold by the retailer in 3 days =  10 packs

total number of pens in the 10 packs = 48 x 10 = 480 pens

let the number of pens sold on Monday = x

let the number of pens sold on Sunday = y

let the number of pens sold on Tuesday = z

He sold twice as many pens on Sunday than on Monday

y = 2x equation (1)

He sold 55 pens fewer on Tuesday than on Sunday

y = z + 55 equation (2)

total number of pens sold in the three days

y + z + x = 480  equation (3)

from equation (1) make x the subject of the formula

x = y/2

from equation (2) make z the subject of the formula

z = y - 55

substitute the value of x, and z into equation (3)

y + y/2 + y - 55 = 480

2y + y/2 = 480 + 55

5y/2 = 535

5y = 535 x 2

5y = 1070

y = 1070 / 5

y = 214

The number of pens sold on Monday is:

x = y / 2

x = 214 / 2

x = 107 pens

Thus, the number of pens sold on Monday is 107 pens

apex answer is: true.