What does this rebus mean?

O
N
C
E
TIME

Can you place six X (crosses) in below board without making three in a row in any way ?

Can you find the odd one out from the below words ?

First Second Third Forth Fifth Sixth Seventh, Eighth Nine Ten Eleven Twelve.

A bomb goes off.
Carnage.
One person, only a few feet away, survives! How can this be?

In the Mexico City area, there are two Houses H1 and H2. Both H1 and H2 have two children each.
In House H1, The boy plays for Mexico Youth academy and the other child plays baseball.
In House H2, The boy Plays soccer for his school in Mexico and they recently have a newborn.

Can you prove that the probability of House-H1 having a girl child is more than that of House-H2?

1 + 9 + 8 = ?
considering, 28 + 8 + 92 = 10

The husband and wife were jogging in the morning. To match every two steps of the husband, the wife required three steps. If Both of them start with the here right foot. After how many steps do their left foot be together?

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

Find the missing number in the series below

13 -21 34 -55 ? -144

If we add four times the age of John four years from now to five times his age five years from now we get ten times his current age.

How old will John be two years from now?