Mathnasium Word Problem: Birds vs Squirrels

It's been such a warm winter that Spring has always seemed ready to spring! We've had shoots ready to bloom; and bugs flying around except for a few cold spells! Our grass has been green all winter, and we've even had a dandelion! Spring -- and it will be Summer quickly -- is definitely here. Birds have been flying around the neighborhood all "winter." Perhaps we should feed them... such “peckish” little creatures! But you'll need a good bird feeder, preferably one that is squirrel proof.

See if you can solve this week’s bird feeder word problem and after the video for the answer. You never know when you might need to apply these calculations for your own bird feeder building efforts! Look at this DIY site for some easy fun and creative ideas.

It takes Ruby 26 minutes to build one bird feeder. If she needs to build seven bird feeders and has already finished three, how much longer will it take Ruby to finish the bird feeders?

Follow these instructions to build a beautiful quick and easy pie tin bird feeder shown above. The cap may make it squirrel proof, but a smart squirrel will learn to jiggle the line and shake out the seeds! Perhaps squirrel proofing may become your big engineering challenge that balances your artistic bird feeder designing.

This is another whole-and-parts question. The whole asks for 7 bird feeders, but Ruby has built 3 parts. Hence, she needs to build 7 - 3 = 4 more bird feeders. Next, how much longer does it take to build those 4 if each takes 26 minutes? Multiply 4 and 26 to get the answer; but 26 isn't nice! Rather than the standard multiplication method, we've got a couple of good strategies to do this.

The first is to decompose 26 into 20 + 6 and multiply each by 4 to get the partial products and sum them 80 + 24 = 104. This is the standard method in "disguise."

The second is to decompose 26 into "compatible" numbers 25 + 1 and multiply each 4 to get partial products 100 + 4 =104. Compatible numbers are familiar number sets, such as 25 x 4 because "4 quarters make a 100 cents!", and 1 x 4 = 4 (of course!).

Both approaches are now taught in "common core" curriculum explicitly as yet more multiplication techniques that must be mastered; and we notice our new students experience some degree of stress having to learn so many "confusingly" different multiplication techniques. At Mathnasium, we have the luxury of understanding each child individually; and we teach these alternatively approaches gently integrated with other problem sets; when we're comfortable that your child can understand their rational.

Finally, the 104 minutes to build the 4 remaining bird feeders, is also 60 minutes + 44 minutes = 1 hour and 44 minutes.

What's more fun, building the feeders or thwarting the squirrels? Let us know!

Contact:
Ruby Yao and Benedict Zoe, Mathnasium of Fort Lee
201-969-6284 (WOW-MATH), fortlee@mathnasium.com
246 Main St. #A
Fort Lee, NJ 07024
Happily serving communities of Cliffside Park, Edgewater, Fort Lee, Leonia, and Palisades Park.
Great sources:
http://www.birdsandblooms.com/...
http://www.diyncrafts.com/3515...