Readers like you keep news free for everyone.

More than 5,000 readers have already pitched in to keep free access to The Journal.

For the price of one cup of coffee each week you can help keep paywalls away.

Support us today
Not now
Dublin: 18°C Monday 15 August 2022

Science Week: The answers so you can enjoy your Friday night

Have you been taking part in our Brainteaser series? See how many you’ve got right.

Image: Farm animals via Shutterstock

EVERY DAY DURING Maths Week, we came up with a little puzzle to wreck your head.

And the scientists of Ireland wanted in. So to celebrate Science Week, which launched last Sunday, we came up with a different brainteaser for you each evening this week.

But we didn’t want to ruin your Friday – or the rest of the weekend. So here are all the answers.


Question: You have a string-like fuse that burns in exactly one minute. The fuse is inhomogeneous, and it may burn slowly at first, then quickly, then slowly, and so on. You have a match, and no watch.How do you measure exactly 30 seconds?

Here’s your answer…

Light the fuse at both ends.


Question: I am a chemical symbol for an element.This element was discovered in 1824.I am a Spanish word without the accent. Reverse me so I become a form of a common verb. What symbol am I?

Here’s your answer…

Si for silicon.


Question: How can you throw a ball as hard as you can and have it come back to you even if it doesn’t hit anything, there is nothing attached to it and no one else catches or throws it?

Here’s your answer… 

Throw it straight up into the air.

Question: You’re a farmer and you’re going to buy some animals. At the market you can buy: Horses for €10 each, goats for €1 each and a bunch of 8 ducks for €1.

The aim is to acquire 100 animals at the cost of €100, what is the combination of horses, goats and duck that allows you to do this? (You must buy at least one of each.)

Here’s your answer…

7 horses, 21 goats and 9 bunches of ducks.

Making a difference

A mix of advertising and supporting contributions helps keep paywalls away from valuable information like this article.

Over 5,000 readers like you have already stepped up and support us with a monthly payment or a once-off donation.

For the price of one cup of coffee each week you can make sure we can keep reliable, meaningful news open to everyone regardless of their ability to pay.


Question: You have to get a bag of grain, a chicken and a fox across a river. You are only able to bring one item over at a time.How do you get all three items across safely, without the fox eating the chicken or the chicken eating the grain?

Here’s your answer… 

Take the chicken across.
Come back with the boat empty besides yourself.
Take the grain across.
Take the chicken back.
Take the fox across.
Come back with the boat empty besides yourself.
Take the chicken across.

Question: On what three parts of the body does hair not grow?

Here’s your answer…

Palms of hands
Soles of feet

How did you do?

See the questions here>

Read next: