Maths puzzles

[kingsley]

I found this in my maths textbook earlier. They are taken from old School Mathematics Challenge papers. Most people will probably find these easy as they are aimed at intelligent 14-16 year olds, but I thought they might give people something to do. They caom with multiple choice in the book, but with the exception of number 7, I think they are all manageable without. I thought of Gill when I read them through!

1. Weighing the baby at the clinic was a problem. The baby would not keep still and caused the scales to wobble. So I held the baby and stood on the scales while the nurse read off 78 kg. Then the nurse held the baby while I read off 137kg. Finally I held the nurse while the baby read off 137kg. What would be the combined weight of nurse, baby and me (in kilograms)?

2. Baby's nearly 1 now. We've worked out how to weigh her, but nurse and I still have trouble measuring her height. She just will not stand up straight against our measuring chart. In fact she can't stand up at all yet! So we measure her upside down. Last year, burse held Baby's feet, keeping them level with the 140 cm mark while I read off the mark at Baby's head: 97cm. This year it was my turn to hold the feet. Being taller then the nurse I held them against the 150cm mark and nurse read off 84 cm at Baby's head. How many centimetres ahs baby grown inher first year?

3. Baby's now 2 and we have decided to call her Gill. Getting her to recognise her name has proven difficult so we put the letters G, I, L, L on separate building blocks. She loves arranging them, but rarely gets them in the right order. One day she produced every possible four letter word out of them. How many different words did she produce?

4. This year was Gill's fourth birthday. The highlight of the party was the game of musical chairs. The game got down to herself, nurse and me. Only two chairs left. The music stopped and we all piled onto the nearest chair, some on top of one another. If Gill's bottom was firmly in contact with one of the two chairs, in how many different ways could this have happened?

5. (not for any freestyle spellers!) Gill has now started primary skool and is learning to spell. We got her to help righting out this question for us. We gave her a score out of 100 to start with and deducted 10% of her running total every time we found a word spelt rong. What was her final score?

6. Gill is just 6 and boasts she can count up to 100. However, she often mixes up nineteen and ninety and so jumps staright from nineteen to ninety one. How many numbers does she miss out?

7. Gill arranges the fingers on her right hand so that her thumb points upwards (U), her first finger points north (N) and her second finger points west (W). This is written as TU 1N 2W. she then keeps her fingers fixed like this, but twists her arm and wrist around. Which of the following arrangements can she not acheive? (D=down, S=south, E=east)

A. TD 1N 2E B. TN 1D 2W C.TS 1E 2U D. TE 1U 2S E. TW 1S 2D

8. Last year's carnival procession was 1.5 km long. The last float set off and finished 45 minutes after the first float. Just as the first float reached, young Gill escaped and ran to the other end of the processiona and back in the time it took for hapf of the procession to pass us. Assuming Gill ran at a constant speed, how fast did she go?

NOTE: I do not have the answers.

Enjoy!

[giraffe]

They look easier than 11+ questions to me.

[SparkOut]

I think the biggest puzzle is why it took two years to decide on a name?

[Scurra]

What about this precocious baby who can read scales?

[evilkeen]

Then the nurse held the baby while I read off 137kg. Finally I held the nurse while the baby read off 137kg.

So you weigh the same as the baby?!

[clvrlad]

talk about the ooh ahhh bird

[MBH]

I'll look at these later, but that's a nasty trick in number 3