What is one and one fourth plus two and three over twenty plus three fifth?

Answer 1

When working with mixed numbers, it is usually easier to convert them to improper fractions, do the operations, and then to convert any resulting improper fraction back to a mixed number:

1 1/4 + 2 3/20 + 3/5

= (1×4+1)/4 + (2×20+3)/20 + 3/5

= 5/4 + 43/20 + 3/5

= (5×5)/(4×5) + 43/20 + (3×4)/(5×4)

= 25/20 + 43/20 + 12/20

= (25+43+12)/20

= 80/20

= 4

Answer 2

4

1 1/4 + 2 3/20 + 3/5

First convert the mixed numbers to improper fractions. To do this, multiply the denominator by the whole number and add the numerator. Place the result over the denominator.

1 1/4 = (4 x 1 + 1)/4 = 5/4

2 3/20 = (20 x 2 + 3)/20 = 43/20

In order to add or subtract fractions, they must have the same denominator, called the least common denominator (LCD), which is the same as the least common multiple (LCM).

Both 4 and 5 can go evenly into 20, so 20 is the LCD. Multiply 5/4 and 3/5 by a fraction equal to 1, such as 3/3 = 1, that will give both fractions the denominator 20. Multiplying by a fraction equal to 1 maintains the value of the fraction.

5/4 x 5/5 + 43/20 + 3/5 x 4/4 =

25/20 + 43/20 + 12/20 =

(25 + 43 + 12)/20 =

80/20

Reduce by dividing the numerator and denominator by 4.

(80/4)/(20/4) = 20/5 =4

Answer 3

It is 4.