Addition with Regrouping: 78 + 45

Addition with Regrouping Calculator

What is 78 + 45?

Answer

78 + 45 =

123

The sum is longer than the addends: 2 carries — into the tens and the hundreds; the last one makes a new digit

78 + 45 in a column. Carries are the small circled digits above the columns.
		1carry	1carry
			7	8
	+		4	5
		1	2	3

Column by column: 78 + 45

Ones: 8 + 5 = 13 — write 3, carry 1.
Tens: 7 + 4 + 1 = 12 — write 2, carry 1.
Hundreds: the carried 1 — write 1.

78 + 45 = 123

Second check: 123 − 78 = 45

Similar examples to practise

Related Calculations

123 − 45 = 78 - Subtraction with Regrouping

See Also

Subtraction with Regrouping Calculator - Column subtraction step by step, with borrowing across zeros
Long Multiplication Calculator - Column multiplication with partial products, step by step
Long Division Calculator - Step-by-step long division with detailed explanation
Adding Fractions Calculator - Add fractions, mixed numbers and whole numbers step by step

Recalculate with different values ↑

Column additions with 45

Example	Sum
52 + 45	97
54 + 45	99
58 + 45	103
63 + 45	108
65 + 45	110
67 + 45	112
69 + 45	114
71 + 45	116
74 + 45	119
76 + 45	121
78 + 45	123
83 + 45	128
85 + 45	130
89 + 45	134
92 + 45	137
94 + 45	139
98 + 45	143
105 + 45	150
136 + 45	181
172 + 45	217

FAQ

What is 78 + 45?

78 + 45 = 123

How do you check that 78 + 45 = 123?

Subtract one addend from the sum: 123 − 45 = 78, and 123 − 78 = 45. Getting the other addend back means the sum is right.

How many carries are there in 78 + 45?

2 carries: every time a column added up to 10 or more, its ones digit was written and 1 was carried to the next column on the left.

Is 45 + 78 the same as 78 + 45?

Yes. Addition is commutative, so both give 123; the column looks the same with either number on top.

See Also