1. use front-end estimation to estimate the sum 8.86 + 9.43 + 5.75
a. 9+10+6+2=27
b. 10+10+10+2=32
c. 8+9+5+1=32
d. 8+9+5+2=24
2. find the estimated difference. round to the nearest whole number 83.92-47.23
a. 37
b. 47
c. 50
d. 30

1. Option D.

2. Option A.

Step-by-step explanation:

1. You need to follow these steps in order to estimate the sum of :

Step 1: Add the digits in the ones places of the whole numbers (these are: 8, 9 and 5).

Step 2: Round the decimals to the nearest whole number:

 Step 3: Add them together:

2. The procedure to estimate  the difference of is:

Rounded to the nearest whole number:

x = central angle apc = measure of minor arc ac

the two angles x and 30 add to 180, so x+30 = 180 and x = 180-30 = 150. the measure of minor arc ac is 150 degrees.

what we need to do from here is find the circumference and then multiply it by x/360 since there are 360 degrees in a circle. in this case, x = 150, so x/360 = 150/360 = 15/36 = 5/12. the shortest distance along the curve from a to c is 5/12 of the distance around the entire circle (aka circumference)

c = circumference

c = pi*d

c = pi*24

c = 24pi

now multiply this by 5/12 to get

distance along minor arc ac = (5/12)*(circumference)

distance along minor arc ac = (5/12)*(24pi)

distance along minor arc ac = 10pi

the formula you can use is

l = (x/360)*pi*d

with

l = length of minor arc

x = central angle

d = diameter

which essentially is the steps we took though a bit differently.

77

step-by-step explanation: