Question

2+5=336,3+6=720,4+7=1120,5+8=?​

Answer 1

Given:

2 + 5 = 336, 3 + 6 = 720, 4 + 7 = 1320

We have to find, the value of 5 + 8 = ?​

Solution:

The pattern follow:

$(Sum of numbers)^{3}$ - (Sum of numbers).

336 = $(2+5)^{3}$ - (2 + 5) = $7^{3}$ - 7

= 343 - 7 = 336

720 = $(3+6)^{3}$ - (3 + 6) = $9^{3}$ - 9

= 729 - 9 = 720

1320 = $(4+7)^{3}$ - (5 + 8) = $11^{3}$ - 11

= 1331 - 11 = 1320

Similarly,

?​ =  $(5+8)^{3}$ - (5 + 8) = $13^{3}$ - 13

= 2197 - 13 = 2184

∴ Missing number (?) = 2184

Thus, if 2 + 5 = 336, 3 + 6 = 720, 4 + 7 = 1320, then "5 + 8 = 2184".

Answer 2

5 + 8 = 2184

Step-by-step explanation:

The formula followed here is:

a + b = c = (a + b)³ - (a + b)

2 + 5 = 336

⇒ (2 + 5)³ - (2 + 5) = (7)³ - 7 = 343 - 7 = 363

3 + 6 = 720

⇒ (3 + 6)³ - (3 + 6) = (9)³ - 9 = 729 - 9 = 720

4 + 7 = 1120

⇒ (4 + 7)³ - (4 + 7) = (11)³ - 11 = 1331 - 11 = 1320

5 + 8 =

⇒ (5 + 8)³ - (5 + 8) = (13)³ - 13 = 2197 - 13 = 2184

∴ 5 + 8 = 2184