Estimation ((Reference))

Estimation is the process of determining an expected value of a computation.

Estimation By Rounding ((Reference))

The rounding technique estimates the result of a computation by rounding the numbers involved in the computation to one or two nonzero digits. For example, 512 + 896512 + 896 size 12{"512 "+" 896"} {} can be estimated by 500 + 900 = 1,400500 + 900 = 1,400 size 12{"500 "+" 900 "=" 1,400"} {}.

Cluster ((Reference))

When several numbers are close to one particular number, they are said to cluster near that particular number.

Estimation By Clustering ((Reference))

The clustering technique of estimation can be used when

Distributive Property ((Reference))

The distributive property is a characteristic of numbers that involves both addition and multiplication. For example,
3(4 + 6)= 3 ⋅ 4 + 3 ⋅ 6 = 12 + 18 = 303(4 + 6)= 3 ⋅ 4 + 3 ⋅ 6 = 12 + 18 = 30 size 12{3 \( "4 "+" 6" \) =" 3 " cdot " 4 "+" 3 " cdot " 6 "=" 12 "+" 18 "=" 30"} {}

Estimation Using the Distributive Property ((Reference))

The distributive property can be used to obtain exact results for a multiplication.
For example,
15 ⋅ 23 = 15 ⋅ ( 20 + 3 ) = 15 ⋅ 20 + 15 ⋅ 3 = 300 + 45 = 345 15 ⋅ 23 = 15 ⋅ ( 20 + 3 ) = 15 ⋅ 20 + 15 ⋅ 3 = 300 + 45 = 345 size 12{"15 " cdot " 23 "=" 15 " cdot \( "20 "+" 3" \) =" 15 " cdot " 20 "+" 15 " cdot " 3 "=" 300 "+" 45 "=" 345"} {}

Estimation by Rounding Fractions ((Reference))

Estimation by rounding fractions commonly rounds fractions to 1414 size 12{ { {1} over {4} } } {}, 1212 size 12{ { {1} over {2} } } {}, 3434 size 12{ { {3} over {4} } } {}, 0, and 1.
For example,
512+516512+516 size 12{ { {5} over {"12"} } + { {5} over {"16"} } } {} can be estimated by 12+14=3412+14=34 size 12{ { {1} over {2} } + { {1} over {4} } = { {3} over {4} } } {}