Daily 30 Seconds - Dec 02

Can you solve 3 mathematical questions in 30 seconds? Click 'Start' to see the number you're starting with, and then follow the instructions until you get to the end.

Easy

+13

×2

+10

HALVE

−13

SQUARE

+16

÷5

−8

?

Puzzle Copyright © Kevin Stone

Medium

+4

÷5

−1

×6

−16

DOUBLE

+2

x 1/3

HALVE

?

Puzzle Copyright © Kevin Stone

Hard

−11

x 31/3

×2

x 70%

x 5/7

−2

x 25%

−3

SQUARE

?

Puzzle Copyright © Kevin Stone

Notes

All daily items change at midnight GMT.

• HALVE   divide by 2 (e.g. 10 ÷ 2 = 5)
• DOUBLE  multiply by 2 (e.g. 10 x 2 = 20)
• SQUARE  times by itself (e.g. 10 x 10 = 100)
• CUBE    times by itself twice (e.g. 10 x 10 x 10 = 1,000)
• x ³/₅   find three fifths (e.g. ¹/₅ of 15 = 3, so ³/₅ = 9)
• x 2¹/₃  find two and a third (e.g. 2 ¹/₃ of 15 = 2 x 15 + 5 = 35)
• x 10%   find 10% (e.g. 10% of 80 = 8)
• √       find the square root (e.g. the square root of 100 is 10)

I have deliberately chosen not include the answers. You can use a calculator to see the value at each stage of the calculation.

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