A shop is offering a discount on pens. If you buy 10 pens at the regular price, you can get the next 10 for half off. A customer came in and bought 20 pens for $30. What's the regular price of one pen in dollars?

Let p be the cost of a full-priced pen.

We know that the first 10 pens are sold at the regular price, so they cost 10*p.

We also know the any pens purchased after the first 10 are half-price, so they cost (20 pens - 10 pens) * p/2 on those.

If we add the cost of the first 10 pens and the pens sold at half-price it equals the total purchase of price of $30=10*p + (20-10)*p/2.

Thus, $30 = 10*p + 10 * p/2.

And, $30 = 10 *p + 5*p.

So, $30 = 15* p.

Finally, p=$

<<2=2>>2. #### 2 Thirty students run in a charity race to raise money for the hurricane victims. Ten of the students raised $20 each. The rest of the students raised $30 each. How much did the students raise in all? Ten students raised a total of $20 x 10 = $<<20*10=200>>200. There are 30 - 10 = <<30-10=20>>20 students who raised $30 each. Twenty students raised a total of $30 x 20 = $<<30*20=600>>600. Therefore, the students raised a total of $200 + $600 = $<<200+600=800>>800. #### 800 The Lady Eagles basketball team scored a total of 311 points in 5 games. Some players combined for 188 points. Lisa, Jessie, and Devin equally scored the rest. How many points did Jessie score? Lisa, Jessie, and Devin scored 311 - 188 = <<311-188=123>>123 points 123/3 = <<123/3=41>>41 Jessie scored 41 points. #### 41 Juan needs 10 half-gallons of milk to bake 40 cookies with. How many half-gallons of milk does Juan need to bake 200 dozen cookies? If 10 half-gallons of milk bake 40 cookies, then one half-gallon of milk bakes 40/10 = 4 cookies. If one half-gallon of milk bakes 4 cookies. to bake 200 cookies, you'll need 200/4 = <<200/4=50>>50 half-gallons of milk #### 50 Patrick buys a season pass for each of his sons to visit the local amusement park as often as they want. The passes were $100.00 each. The oldest son went to the park 35 times over the summer and the youngest went 15 times. What was the cost per trip to the park? Patrick bought 2 tickets at $100.00 each for a total of 2*100 = $<<2*100=200.00>>200.00 The oldest son went 35 times and the youngest went 15 times for a total of 35+15 = <<35+15=50>>50 trips The tickets cost $200.00 and together, the boys went to the park 50 times so each trip cost 200/50 = $<<200/50=4.00>>4.00 #### 4 300 cows in a field are made up of male and female cows. There are twice as many females as males. Half the females are spotted, and half the males have horns. How many more females with spots are there than males with horns? There are (300/3) x 2 = 100 x 2 = <<300/3*2=200>>200 females cows in the field. There are 200/2 = <<200/2=100>>100 male cows in the field. 200/2 = <<200/2=100>>100 female cows are spotted. 100/2 = <<100/2=50>>50 male cows have horns. There are 100 - 50 = <<100-50=50>>50 more females with spots than males with horns. #### 50 There are three buckets of seeds labeled A, B, and C with 100 seeds. There are ten more seeds in bucket A than in bucket B, and bucket B has 30 seeds. How many seeds are in bucket C? Bucket A has 10 more seeds than bucket B: so there are 10 seeds + 30 seeds = <<10+30=40>>40 seeds in bucket A. Bucket A and bucket B have 40 seeds + 30 seeds = <<40+30=70>>70 seeds together. If there are 100 seeds in all the buckets, then bucket C has 100 seeds - 70 seeds = <<100-70=30>>30 seeds. #### 30 Tony bought 3 lottery tickets and chose identical numbers on each ticket. He finds out that 5 of the numbers on each lottery ticket are winning numbers. If each winning number is worth $20 then how much money, in dollars, has Tony won in total? Across all of the lottery tickets, Tony has a total of 3 lottery tickets * 5 winning numbers per lottery ticket = <<3*5=15>>15 winning numbers. Across all the numbers, he has won a total of 15 winning numbers * $20 per winning number = $<<15*20=300>>300. #### 300 Free Christmas decorations are being given out to families. Each box of decorations contains 4 pieces of tinsel, 1 Christmas tree and 5 snow globes. If 11 families receive a box of decorations and another box is given to the community center, how many decorations have been handed out? Each box contains 4 tinsel + 1 tree + 5 snow globes = <<4+1+5=10>>10 decorations. A total of 11 family boxes + 1 community center box = <<11+1=12>>12 boxes have been given out. So the total number of decorations given out is 10 decorations * 12 boxes = <<10*12=120>>120 decorations. #### 120 Françoise sells pots of lily of the valley to fund humanitarian work. She buys them at €12 each and sells them at a 25% higher cost. How much will she give back to the association by selling 150 pots of lily of the valley? The benefit of selling one pot is 12 * 25 / 100 = €<<12*25/100=3>>3. So, Françoise will give 150 * €3 = €<<150*3=450>>450 to the association. #### 450