Please find my answers below:
Q1) 19 + 15 = 34
A1) True because 1 ten + 1 ten = 20 tens and 9 + 5 = 14. Therefore 34 is the correct answer.
Q2) 34 = 19 + 15
A2) True because this is same as previous number sentence. It is written in a different way.
Q3) 19 + 15 = 15 + 19
A3) True because on both sides of the = sign, same two numbers are getting added.
Q4) 34 = 34
A4) True because on both sides of the = sign, you have same number. You could imagine it as two people having same number of chocolates.
Q5) 19 + 15 = 34 + 0
A5) True because this is just like Q1 with +0 at the end of the right side of the number sentence. 0 does not have any value, also means no extra chocolates.
Q6) 19 + 15 = 0 + 34
A6) True because same as the previous question. Right side of the equation is just flipped around.
Q7) 34 = 16 + 17
A7) False because as we know 19 + 15 = 34. Also 6 + 7 is 13 and not 14.
Q8) 19 + 15 = 21 + 13
A8) True because 21 is 2 more than 19. So next number getting added should be 2 less than the number on the left side, 13 is 2 less than 15.
Q9) 19 + 15 = 20 + 16
A9) False because 20 more than 19 and 16 is 1 more than 15.
Q10) 19 + 15 = 22 + 18
A10) False because same reason as Q9.
Q11) 19 + 15 = 34 + 15
A11) False because 34 is 15 bigger than 19. 15 on left and 15 on right is same.
Q12) 15 + 19 = 20 + 14
A12) True because 20 is 5 more than 15 and 14 is 5 less than 19, so both sides would have same candy canes and chocolates if we imagine as candy canes and chocolates which my sister and I would get.
Second Set
Q1) 346 + 289 = 349 + 286
A1) True because 349 is 3 more than 346 and 286 is 3 less than 289.
Q2) 727 + 581 = 581 + 727
A2) True as they are same number sentence on both sides of =
Q3) 478 - 192 = 480 - 194
A3) True - 480 is two bigger than 478 and 194 is two bigger than 192.
Q4) 831 - 344 = 841 - 334
A4) Fasle - Think in terms of part whole model. The whole number on both sides are not same. 841 is 10 more than 831. So the take away number should be 10 more from the whole number 841. But 334 is not 10 more than 344.
Q5) 346 + 289 = 345 + 288
A5) False because both sides do not have the same numbers. And left is the greatest.
Q6) 727 + 581 - 581 = 727
A6) True. My sister has y amount of chocolates. I have x amount of chocolates. I put my x amount of chocolates next to my sister's y amount. Then I take my x amount of chocolates back home for no actual reason. So she has her original y amount left.
Q7) 831 - 344 + 346 = 831
A7) False - There is z amount of chocolates. 344 is taken away from that and 346 is added back which 2 more than what was taken away. so z becomes z + 2 which means you would have 2 chocolates more than what you had initially.
Q8) 169 + 672 = 2041
A8) False - It is not even making 1000, 600+100 = 700 and 69 + 72 will be something in 100s.