Friday, April 29, 2016

Math Monster Story 3 - The Case of the Mixed Up Seeds

Math Monster Story 3 - The Case of the Mixed Up Seeds

When you last saw Marvin, the Math Monster, you had just finished feeding his cute dragon friend, Digit.  Then after some fun math questions, you headed outside for the day.  Where Marvin lives it's springtime and finally warm enough to start sowing the seeds for his vegetable garden.  You walk together until you come to some beautiful rolling hills on the far side of the castle where a small plot of ground has been tilled and looks ready for planting!

Marvin bounces excitedly and asks, "Ready to get to work?  I love fresh veggies in the summer, and now is the time to start planting the seeds!"  You nod enthusiastically, and Marvin hands you some tools and gloves.


Then Marvin reaches into his pockets and pulls out a handful of seeds in all different shapes and sizes.  It looks like a complete mess!

You groan loudly, and Marvin asks, "What's wrong?"
"The seeds are all mixed up!  How will you know which seeds are which?" you reply.
"Don't worry!  I have a system!" Marvin says, confidently.  "You can help me sort them all out and plant them.  We just need to do a little math!  Some of these are going to be tough, but let's take our time, have fun, and work on them together.  Take a deep breath of that fresh air, feel the warm spring sunshine on your face and the cool soil between your fingers."

Sorting Them Out

Warm-up: For my climbing vines, I have the same number of seeds as letters in the veggie's name.  I have 3 pea seeds because there are 3 letters in "pea".  How many bean seeds do I have?  How many cucumber seeds?  Which do I have more of?

Jog: For my red veggies, I know I have 5 tomato seeds.  I have twice as many radish seeds as tomato seeds and twice as many red pepper seeds as radish seeds.  How many radish and red pepper seeds do I have?  How many red veggie seeds do I have all together?

Sprint: For my root veggies, I know I have an odd number of potato seeds, an even number of beet seeds, and an odd number of carrot seeds.  I have 1 less beet seed than carrot seeds, and the number of potato seeds is exactly half the total number of all three kinds of seeds combined.  The total number of seeds is 18.  How many do I have of each?

Row, Row, Row

Warm-up: I want the tallest plants in the northern rows so they don't cast shadows on the shorter plants.  Which is taller and by how much?  A 40" tomato plant or a 30" pepper plant?

Jog: I want to have 3 rows of corn with 10 seeds in each row.  How many corn seeds will I have planted?

Sprint: My beans will grow ½" per day.  How tall will they be in 8 weeks?

Just For Fun: Germination rate means how many seeds out of a group of seeds will actually sprout.  If watermelon seeds have an 80% germination rate, how many seeds should I plant if I need 12 watermelon plants?
Wow, that was a lot of math, but now all the seeds are sorted and planted!  You and Marvin give everything a good watering and head back to the castle for lunch.

The end...for now!

 

Stay tuned for more activities, including more in this series by following us on Twitter or Facebook.

Good night and...Mind the nap!


Answers

 

Sorting Them Out
WU: 4 bean seeds, 8 cucumber seeds.  More cucumbers than beans.
J: 10 radish seeds, 20 red pepper seeds.  35 seeds all together (5+10+20).  30 if you know tomatoes are actually fruits!  ;-)
S: 5 carrot seeds, 4 beet seeds, 9 potato seeds

Row, Row, Row
WU: 40" tomato is taller by 10" (40-30)
J: 30 corn plants (10x3 or 10+10+10)
S: 8 weeks has 56 days.  At a rate of ½" every day, it is 1" every 2 days.  After 56 days, it would be 28" tall.
JFF:15 plants needed.  80% is the same as 8 out of 10, which is the same as 4 out of 5, which is the same as 12 out of 15.  Also the opposite of 80% (8/10) is 10/8 which is 1.25, so if you take 12 and add .25 of 12 (which is 3), you get 15.