the answer to 20 + 20 = 40
the sum for 20 + 40 + 70 + 80 = 210
20 of them
The sum of the first 20 even numbers... is 110
-- Drop 20 pennies or little stones onto a small patch of bare ground. -- Drop 40 more pennies or little stones onto the same place. Do it carefully, so that you don't scatter them. -- Pick up all of the pennies or little stones and count them. The number you have is the sum of 20 and 40.
It is: 20+20 = 40
the answer to 20 + 20 = 40
the sum for 20 + 40 + 70 + 80 = 210
20+20=40 20x20=400
The sum of two numbers between 20-40 is 58. The difference is 12
20.
20 and 20.
440
2,4,8,10 and 16 are factors of 400.
20 of them
The sum is: 23+29+31+37 = 120
The mass number of an atom is the sum of the protons and neutrons in its nucleus. Therefore, for an atom of calcium with 20 protons and 20 neutrons, the mass number would be 40.