mummyDear

mummy here, mummy there, mummy mummy everywhere Brain Exercise 1 April 27, 2007

Filed under: Learning — mummydear @ 6:05 pm

Continuation fr post: Problem Solving – Heuristic Approach

Come, do some Maths exercises here. Note tt the questions here are applicable to any primary levels, not jus P1/P2.

Cannot use algebra or equation huh.

1) Lily has the same number of ten-cent coins and fifty-cent coins. Their total value is \$30. How many coins has Lily?

2) A chicken and a duck cost \$14. The duck cost \$4 more than the chicken. Find the cost of the duck.

3) 6 similar blocks are used to form a stair of 3-steps high. How many blocks are needed to form a stair of 9-steps high?

OK, will update the workings here when I find time to draw them out. Meanwhile, u may wanna post yr workings at the comments. Hv fun!

***** Solutions (Updated on 9 May 07) *****  9 Responses to “Brain Exercise 1”

1. rolypolygohly Says:

1) trial and error – start with any equal qty of 10- and 50-cent coins and multiply qty with denomination and add them until u get the answer = 50-50

2) use model – draw 1 equal unit each for chix and duck and extension for duck rep +4. both units + ext = 14. 2 equal units = 14-4 = 10. 1 unit = 5, so duck = 5 + 4 (ext) = 9

3) drawing – 3-steps with 6 blocks = 3 for base and -1 for each subsequent steps = 3+2+1 = 6. So 9 steps = 9 for base and -1 for each subsequent steps = 9+8+7+6+5+4+3+2+1=45

2. jy Says:

1st qns: draw e table n do trial n error

2nd qns: model

3rd qns: draw diagram!!!

3. mummydear Says:

Vy good.

4. bibo Says:

1)same as dem…

2)find d equal amount=\$14-\$4
=\$10
find chicken=\$10/2
=\$5
duck=\$5+\$4
=\$9

3)3 steps=6 blocks
9 steps=9/3*6
=18 blocks!!!

5. bibo Says:

1)same as dem…

2)find d equal amount=\$14-\$4
=\$10
find chicken=\$10/2
=\$5
duck=\$5+\$4
=\$9

3)3 steps=6 blocks
=3+2+1
9 steps=9+1+8+2+7+3+6+4+5
=45

6. bibo Says:

read rolypolygohly de den understand wat d qns means…

7. mummydear Says:

Hello, hv updated the solutions here. But I can see tt Roly, JY and Bibo oledi vy competent liao.

8. Tania Says:

just came across your blog when i was googling for heuristic mathematical methods.

for the coins question, there’s an easier method:

since no. of \$0.10 = no. of \$0.50, the value of a single set is \$0.10+\$0.50 = \$0.60.

therefore, all you need to do is to divide \$30 by \$0.60 and you’ll get 50 sets.

hence, there are 50 x \$0.10 & 50 x \$0.50.

this method saves a lot of time/effort as compared to guess & check. the latter method should be the last resort in trying to solve such problems.

9. jaws Says:

Yes Tania, thanks for providing another better solution.

The abv sums were examples given to illustrate different methods of solving Maths problem by my girl’s school, and the workshop has helped me to teach my girl more effectively using these methods tt are easier than using equations.