Browse Teasers
Search Teasers

The Four-Stone Ring

Math brain teasers require computations to solve.

 Puzzle ID: #8395 Fun: (2.76) Difficulty: (2.51) Category: Math Submitted By: skaven Corrected By: Dave

While Christmas shopping, I chose a gold ring set with stones for my mother.

A ring set with 2 rubies and a diamond would have cost £3,000. One set with 4 amethysts and a diamond would come to £2,000. And 3 emeralds, 1 amethyst and a diamond would be £1,400.

Being a thoughtful son, I chose a ring that would have sentimental value. As my mother called her children Ellen, David, Richard and Andy, I have chosen a ring with one of each stone, to represent her children's names.

How much will my ring containing 1 emerald, 1 diamond, 1 ruby and 1 amethyst cost me?

The three rings can be expressed as:

0E + 0A + 2R + 1D = £3,000
0E + 4A + 0R + 1D = £2,000
3E + 1A + 0R + 1D = £1,400

If we multiply the first line by 1.5 and divide the second line by 2, then total all three rings we get:

0E + 0A + 3R + 1.5D = £4,500
0E + 2A + 0R + .5D = £1,000
3E + 1A + 0R + 1D = £1,400
_________________________
3E + 3A + 3R + 3D = £6,900

£6,900 / 3 = £2,300

From this, we can see that a ring with one of each stone will cost me £2,300.

Hide

What Next?

See another brain teaser just like this one...

Or, just get a random brain teaser

If you become a registered user you can vote on this brain teaser, keep track of
which ones you have seen, and even make your own.