You got:
14.33 | + | (1 x 10) | = | 21.23 |
time | + | (wrong x 10) | = | score |
3 scores max per player; No foul language, show respect for other players, etc.
Name | Score | Date | ||
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1 | ||||
2 | ||||
3 | ||||
4 | ||||
5 | ||||
6 | ||||
7 | ||||
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9 | ||||
10 |
Game: ROCK FALL
Aim: Smash all the falling rocks
Method:
Click / tap on each falling rock. Answer the question in the box as quickly as you can.
There are only 4 questions in this game so it is quite short... if you can get those rocks!
Your final score is based on number of questions answered right / wrong, and the time taken.
Number bonding is a method for recognizing common combinations of numbers that add to a specific target number. In this topic we are looking at pairs of numbers that bond to 100. So, an obvious pair you might think of is:
50 + 50 = 100
Obviously there are many other multiples of 10 that also bond to 100:
40 + 60 = 100
80 + 20 = 100
10 + 90 = 100
One thing you will notice with the multiples of 10 is that we could knock off the final zero and think about number pairs that bond to 10. You will also notice that we can play around with these bonds to derive related facts - for instance:
30 + 70 = 100
100 = 70 + 30
100 - 70 = 30
100 - 30 = 70
Now, let's think about numbers which aern't multiples of 10 like 34 or 59. One way to quickly get their number bond pair to 100 is to work the units first and then figure out the tens. So, for 34, take the unit 4, bond it to 10 with a unit 6. This pushes the tens 3 to a tens 4. Now figure the tens bond of 4 to make 100 which is 6. So the answer is 66.
34 + β’ = 100
30 + 4 + β’ + 6 = 100
30 + 4 + 60 + 6 = 100
So, ... 34 + 66 = 100
Consider another example, say 22:
22 + β’ = 100
20 + 2 + β’ + 8 = 100
20 + 2 + 70 + 8 = 100
So, ... 22 + 78 = 100
So knowing your number bonds, or knowing how to quickly work out number bonds can massively speed up your mental arithmetic.
With our Rock fall math game you will be practicing the topic "Number bonds to 100" from 2nd grade / Addition / Number bonding. The math in this game consists of 22 questions that ask you to identify pairs of numbers that sum to a total of 100.
ROCK FALL is based on the road traffic warning sign for falling rocks - a sign that seems a bit less useful than somebody getting up there on that cliff and actually doing something about it... Anyway, the rocks are falling and it is your job to stop them hitting the road below, or at least stopping them hitting the road below too many times and breaking it. Smash the rocks by clicking or tapping on them (not so easy in real life of course) - they will turn into snowflakes and float gently down into nothing.
There are 4 rocks to stop and not much time to do it (if you want to get a good score and get on the leaderboard). This game is fun and fast and requires good reflexes and a good strategy. Plan to break the smaller rocks first if you want a good score because the rocks fall faster as the game progresses. It also helps to decide where on their path you plan to click / tap the rocks.
UXO * Duck shoot * The frog flies * Pong * Cat and mouse * The beetle and the bee
Rock fall * Four in a row * Sow grow * Choose or lose * Mix and match
There are rocks falling from an unstable cliff. You need to break the rocks by clicking / tapping on them...
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