Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

Pages: **1**

**Person****Guest**

How do you work this out?

Three numbers x, y and z have a sum of 1500

x is 30 more than y

y is 3 times a s big as z

-----------------------------------------------------------------------------

And also:

Millie has 40 coloured shapes.

25 are circles and the rest are squares

23 of the shapes are blue and the rest are green

What is the least number of blue circles she can have?

What is the least number of green circles she can have?

Thanks for helping me!

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 21,460

x = y + 30

y = 3z, z=y/3

Therefore, x + y + z = y + 30 + y + y/3 which is equal to 1500.

7y/3 = 1500 - 30 = 1470

y = 1470 x 3/7 = 630

y=630, x=660, z=210.

------------------------

Millie has 40 coloured shapes.

25 are circles and the rest are squares

23 of the shapes are blue and the rest are green

Therefore, 25 are circles and 15 are squares.

23 of the shapes are blue, therefore 17 are green.

The least number of blue circles is 8 and the least number of green circles is 2.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Offline

**Person****Guest**

How did you work out the second question? I just can't get it round m head?

**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 614

"The least number of blue circles is 8" was obtained by assuming that all green shapes are circles, thus 25 - 17 = 8.

Likewise, "the least number of green circles is 2" was obtained by assuming that all squares are green, thus, 17 - 15 = 2.

Offline

Pages: **1**