# What number should be in place of '?'

What number should be put instead of '?'

20  6  7  2  2
20  4  8  1  2
16  2  9  0  2
?   0  10 -  8


The missing number is:

8

Pattern explanation:

Each line can be fit into the formula:
$a = (b \times c) - de$, where the 4th and 5th terms are concatenated.
$20 = (6 \times 7) - 22$
$20 = (4 \times 8) - 12$
$16 = (2 \times 9) - 02$
For the last one:
$? = (0 \times 10) - (-8)$, which evaluates to 8.

• you solved it even faster than that the site let's me accept your answer:)) – yukashima huksay Oct 25 '17 at 14:12
• @aran You probably double-clicked the Accept button - you'll have to re-accept it. – wizzwizz4 Oct 25 '17 at 18:26